Author: "Pattarakijwanich, P." - Searchworks@Jio Institute Digital Library Search Results

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84 results on '"Pattarakijwanich, P."'

1. Detection of two TeV gamma-ray outbursts from NGC 1275 by LHAASO

Author: Cao, Zhen, Aharonian, F., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo., X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The Water Cherenkov Detector Array (WCDA) is one of the components of Large High Altitude Air Shower Observatory (LHAASO) and can monitor any sources over two-thirds of the sky for up to 7 hours per day with >98\% duty cycle. In this work, we report the detection of two outbursts of the Fanaroff-Riley I radio galaxy NGC 1275 that were detected by LHAASO-WCDA between November 2022 and January 2023 with statistical significance of 5.2~$\sigma$ and 8.3~$\sigma$. The observed spectral energy distribution in the range from 500 GeV to 3 TeV is fitted by a power-law with a best-fit spectral index of $\alpha=-3.37\pm0.52$ and $-3.35\pm0.29$, respectively. The outburst flux above 0.5~TeV was ($4.55\pm 4.21)\times~10^{-11}~\rm cm^{-2}~s^{-1}$ and ($3.45\pm 1.78)\times~10^{-11}~\rm cm^{-2}~s^{-1}$, corresponding to 60\%, 45\% of Crab Nebula flux. Variation analysis reveals the variability time-scale of days at the TeV energy band. A simple test by one-zone synchrotron self-Compton model reproduces the data in the gamma-ray band well., Comment: 11 pages, 8 figures, 3 tables
Published: 2024

2. LHAASO detection of very-high-energy gamma-ray emission surrounding PSR J0248+6021

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, J. H., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., Zou, Y. C., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report the detection of an extended very-high-energy (VHE) gamma-ray source coincident with the location of middle-aged (62.4~\rm kyr) pulsar PSR J0248+6021, by using the LHAASO-WCDA data of live 796 days and LHAASO-KM2A data of live 1216 days. A significant excess of \gray induced showers is observed both by WCDA in energy bands of 1-25~\rm TeV and KM2A in energy bands of $>$ 25~\rm TeV with 7.3 $\sigma$ and 13.5 $\sigma$, respectively. The best-fit position derived through WCDA data is R.A. = 42.06$^\circ \pm$ 0.12$^\circ$ and Dec. = 60.24$^\circ \pm $ 0.13$^\circ$ with an extension of 0.69$^\circ\pm$0.15$^\circ$ and that of the KM2A data is R.A.= 42.29$^\circ \pm $ 0.13$^\circ$ and Dec. = 60.38$^\circ \pm$ 0.07$^\circ$ with an extension of 0.37$^\circ\pm$0.07$^\circ$. No clear extended multiwavelength counterpart of this LHAASO source has been found from the radio band to the GeV band. The most plausible explanation of the VHE \gray emission is the inverse Compton process of highly relativistic electrons and positrons injected by the pulsar. These electrons/positrons are hypothesized to be either confined within the pulsar wind nebula or to have already escaped into the interstellar medium, forming a pulsar halo., Comment: 12 pages, 10 figures, Accepted by Sci. China-Phys. Mech. Astron
Published: 2024

3. Constraints on Ultra Heavy Dark Matter Properties from Dwarf Spheroidal Galaxies with LHAASO Observations

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Saiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: In this work we try to search for signals generated by ultra-heavy dark matter at the Large High Altitude Air Shower Observatory (LHAASO) data. We look for possible gamma-ray by dark matter annihilation or decay from 16 dwarf spheroidal galaxies in the field of view of LHAASO. Dwarf spheroidal galaxies are among the most promising targets for indirect detection of dark matter which have low fluxes of astrophysical $\gamma$-ray background while large amount of dark matter. By analyzing more than 700 days observational data at LHAASO, no significant dark matter signal from 1 TeV to 1 EeV is detected. Accordingly we derive the most stringent constraints on the ultra-heavy dark matter annihilation cross-section up to EeV. The constraints on the lifetime of dark matter in decay mode are also derived., Comment: 17 pages, 12 figures, accepted by PRL
Published: 2024

4. Data quality control system and long-term performance monitor of the LHAASO-KM2A

Author: Cao, Zhen, Aharonian, F., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Bian, W., Bukevich, A. V., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, H. X., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, J. H., Fang, K., Feng, C. F., Feng, H., Feng, L., Feng, S. H., Feng, X. T., Feng, Y., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., Hasan, M., He, H. H., He, H. N., He, J. Y., He, Y., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Karpikov, I., Kuleshov, D., Kurinov, K., Li, B. B., Li, C. M., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, Jian, Li, Jie, Li, K., Li, S. D., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, D. B., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Luo, Q., Luo, Y., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, L. J., Pattarakijwanich, P., Pei, Z. Y., Qi, J. C., Qi, M. Y., Qiao, B. Q., Qin, J. J., Raza, A., Ruffolo, D., Sáiz, A., Saeed, M., Semikoz, D., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, D. X., Sun, Q. N., Sun, X. N., Sun, Z. B., Takata, J., Tam, P. H. T., Tang, Q. W., Tang, R., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, Kai, Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, Q. W., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, Y. L., Xing, Y., Xiong, D. R., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, C. Y., Yang, F., Yang, F. F., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, W. X., Yao, Y. H., Yao, Z. G., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zhao, X. H., Zheng, F., Zhong, W. J., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, B. Y., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., Zou, Y. C., and Zuo, X.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract: The KM2A is the largest sub-array of the Large High Altitude Air Shower Observatory (LHAASO). It consists of 5216 electromagnetic particle detectors (EDs) and 1188 muon detectors (MDs). The data recorded by the EDs and MDs are used to reconstruct primary information of cosmic ray and gamma-ray showers. This information is used for physical analysis in gamma-ray astronomy and cosmic ray physics. To ensure the reliability of the LHAASO-KM2A data, a three-level quality control system has been established. It is used to monitor the status of detector units, stability of reconstructed parameters and the performance of the array based on observations of the Crab Nebula and Moon shadow. This paper will introduce the control system and its application on the LHAASO-KM2A data collected from August 2021 to July 2023. During this period, the pointing and angular resolution of the array were stable. From the observations of the Moon shadow and Crab Nebula, the results achieved using the two methods are consistent with each other. According to the observation of the Crab Nebula at energies from 25 TeV to 100 TeV, the time averaged pointing errors are estimated to be $-0.003^{\circ} \pm 0.005^{\circ}$ and $0.001^{\circ} \pm 0.006^{\circ}$ in the R.A. and Dec directions, respectively., Comment: 15 pages, 9 figures
Published: 2024

5. Discovery of Very-high-energy Gamma-ray Emissions from the Low Luminosity AGN NGC 4278 by LHAASO

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, J. H., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., Zou, Y. C., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The first source catalog of Large High Altitude Air Shower Observatory reported the detection of a very-high-energy gamma ray source, 1LHAASO J1219+2915. In this paper a further detailed study of the spectral and temporal behavior of this point-like source have been carried. The best-fit position of the TeV source ($\rm{RA}=185.05^{\circ}\pm0.04^{\circ}$, $\rm{Dec}=29.25^{\circ}\pm0.03^{\circ}$) is compatible with NGC 4278 within $\sim0.03$ degree. Variation analysis shows an indication of the variability at a few months level in the TeV band, which is consistent with low frequency observations. Based on these observations, we report the detection of TeV $\gamma$-ray emissions from this low-luminosity AGN NGC 4278. The observations by LHAASO-WCDA during active period has a significance level of 8.8\,$\sigma$ with best-fit photon spectral index $\varGamma=2.56\pm0.14$ and a flux $f_{1-10\,\rm{TeV}}=(7.0\pm1.1_{\rm{sta}}\pm0.35_{\rm{syst}})\times10^{-13}\,\rm{photons\,cm^{-2}\,s^{-1}}$, or approximately $5\%$ of the Crab Nebula. The discovery of VHE from NGC 4278 indicates that the compact, weak radio jet can efficiently accelerate particles and emit TeV photons., Comment: 11 pages, 5 figures
Published: 2024

6. LHAASO-KM2A detector simulation using Geant4

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, J. H., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: KM2A is one of the main sub-arrays of LHAASO, working on gamma ray astronomy and cosmic ray physics at energies above 10 TeV. Detector simulation is the important foundation for estimating detector performance and data analysis. It is a big challenge to simulate the KM2A detector in the framework of Geant4 due to the need to track numerous photons from a large number of detector units (>6000) with large altitude difference (30 m) and huge coverage (1.3 km^2). In this paper, the design of the KM2A simulation code G4KM2A based on Geant4 is introduced. The process of G4KM2A is optimized mainly in memory consumption to avoid memory overffow. Some simpliffcations are used to signiffcantly speed up the execution of G4KM2A. The running time is reduced by at least 30 times compared to full detector simulation. The particle distributions and the core/angle resolution comparison between simulation and experimental data of the full KM2A array are also presented, which show good agreement.
Published: 2024
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7. Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

Author: The LHAASO Collaboration, Cao, Zhen, Aharonian, F., An, Q., Axikegu, A., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at $3.67 \pm 0.05 \pm 0.15$ PeV. Below the knee, the spectral index is found to be -$2.7413 \pm 0.0004 \pm 0.0050$, while above the knee, it is -$3.128 \pm 0.005 \pm 0.027$, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -$0.1200 \pm 0.0003 \pm 0.0341$. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components., Comment: 8 pages, 3 figures
Published: 2024
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8. Does or did the supernova remnant Cassiopeia A operate as a PeVatron?

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo., X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: For decades, supernova remnants (SNRs) have been considered the prime sources of Galactic Cosmic rays (CRs). But whether SNRs can accelerate CR protons to PeV energies and thus dominate CR flux up to the knee is currently under intensive theoretical and phenomenological debate. The direct test of the ability of SNRs to operate as CR PeVatrons can be provided by ultrahigh-energy (UHE; $E_\gamma \geq 100$~TeV) $\gamma$-rays. In this context, the historical SNR Cassiopeia A (Cas A) is considered one of the most promising target for UHE observations. This paper presents the observation of Cas A and its vicinity by the LHAASO KM2A detector. The exceptional sensitivity of LHAASO KM2A in the UHE band, combined with the young age of Cas A, enabled us to derive stringent model-independent limits on the energy budget of UHE protons and nuclei accelerated by Cas A at any epoch after the explosion. The results challenge the prevailing paradigm that Cas A-type SNRs are major suppliers of PeV CRs in the Milky Way., Comment: 11 pages, 3 figures, Accepted by the APJL
Published: 2023

9. Very high energy gamma-ray emission beyond 10 TeV from GRB 221009A

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, A., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The highest energy gamma-rays from gamma-ray bursts (GRBs) have important implications for their radiation mechanism. Here we report for the first time the detection of gamma-rays up to 13 TeV from the brightest GRB 221009A by the Large High Altitude Air-shower Observatory (LHAASO). The LHAASO-KM2A detector registered more than 140 gamma-rays with energies above 3 TeV during 230$-$900s after the trigger. The intrinsic energy spectrum of gamma-rays can be described by a power-law after correcting for extragalactic background light (EBL) absorption. Such a hard spectrum challenges the synchrotron self-Compton (SSC) scenario of relativistic electrons for the afterglow emission above several TeV. Observations of gamma-rays up to 13 TeV from a source with a measured redshift of z=0.151 hints more transparency in intergalactic space than previously expected. Alternatively, one may invoke new physics such as Lorentz Invariance Violation (LIV) or an axion origin of very high energy (VHE) signals., Comment: 49pages, 11figures
Published: 2023
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10. The First LHAASO Catalog of Gamma-Ray Sources

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo., X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: We present the first catalog of very-high energy and ultra-high energy gamma-ray sources detected by the Large High Altitude Air Shower Observatory (LHAASO). The catalog was compiled using 508 days of data collected by the Water Cherenkov Detector Array (WCDA) from March 2021 to September 2022 and 933 days of data recorded by the Kilometer Squared Array (KM2A) from January 2020 to September 2022. This catalog represents the main result from the most sensitive large coverage gamma-ray survey of the sky above 1 TeV, covering declination from $-$20$^{\circ}$ to 80$^{\circ}$. In total, the catalog contains 90 sources with an extended size smaller than $2^\circ$ and a significance of detection at $> 5\sigma$. Based on our source association criteria, 32 new TeV sources are proposed in this study. Among the 90 sources, 43 sources are detected with ultra-high energy ($E > 100$ TeV) emission at $> 4\sigma$ significance level. We provide the position, extension, and spectral characteristics of all the sources in this catalog., Comment: 40 pages, 13 figures, 4 tables
Published: 2023
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11. Measurement of ultra-high-energy diffuse gamma-ray emission of the Galactic plane from 10 TeV to 1 PeV with LHAASO-KM2A

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. Y., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Kurinov, K., Li, B. B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Saiz, A., Semikoz, D., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Q. W., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, K., Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, F., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The diffuse Galactic $\gamma$-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this work we report the measurements of diffuse $\gamma$-rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner ($15^{\circ}10$~TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of $-2.99\pm0.04$, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of $\sim3$ than the prediction. A similar spectrum with an index of $-2.99\pm0.07$ is found in the outer Galaxy region, and the absolute flux for $10\lesssim E\lesssim60$ TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations., Comment: 12 pages, 8 figures, 5 tables; accepted for publication in Physical Review Letters; source mask file provided as ancillary file
Published: 2023
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12. A broad-line quasar with unexplained extreme velocity offsets: post-shock outflow?

Author: Rusakov, V., Steinhardt, C. L., Schramm, M., Faisst, A. L., Masters, D., Mobasher, B., and Pattarakijwanich, P.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies
Abstract: The quasar SDSS 0956+5128 exhibits three distinct velocity components with large offsets in emission: the systemic velocity of [O II], [O III] and [Ne III] narrow lines have redshift $z=0.7142$; broad Mg II line is shifted by $-1200$ km s$^{-1}$ with respect to the narrow lines; broad H$\alpha$, H$\beta$ lines are at $-4100$ km s$^{-1}$. We present new Hubble Space Telescope spectra of Ly$\alpha$ and C IV emission lines and high-resolution images of the quasar. The offsets of these lines are consistent with the velocity component of the Balmer emission, and the photometry in optical and near-infrared wavelengths does not show any signs of recent mergers in the host galaxy or irregularities in the location of the quasar. The data do not confirm predictions of the previous most-likely hypotheses involving a special orientation and morphology of the quasar disk, such as in the recoiling black hole scenario, neither it is consistent with accretion disk winds. Instead, based on the cumulative evidence, we propose a new scenario, in which the broad line region is in the state of outflow caused by a strong shock wave, with a supernova as a possible event for producing the shock ejecta., Comment: 15 pages, 4 figures, accepted for publication in ApJ
Published: 2023
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13. Data quality control system and long-term performance monitor of LHAASO-KM2A

Author: Cao, Zhen, Aharonian, F., Axikegu, Bai, Y.X., Bao, Y.W., Bastieri, D., Bi, X.J., Bi, Y.J., Bian, W., Bukevich, A.V., Cao, Q., Cao, W.Y., Cao, Zhe, Chang, J., Chang, J.F., Chen, A.M., Chen, E.S., Chen, H.X., Chen, Liang, Chen, Lin, Chen, Long, Chen, M.J., Chen, M.L., Chen, Q.H., Chen, S., Chen, S.H., Chen, S.Z., Chen, T.L., Chen, Y., Cheng, N., Cheng, Y.D., Cui, M.Y., Cui, S.W., Cui, X.H., Cui, Y.D., Dai, B.Z., Dai, H.L., Dai, Z.G., Danzengluobu, Dong, X.Q., Duan, K.K., Fan, J.H., Fan, Y.Z., Fang, J., Fang, J.H., Fang, K., Feng, C.F., Feng, H., Feng, L., Feng, S.H., Feng, X.T., Feng, Y., Feng, Y.L., Gabici, S., Gao, B., Gao, C.D., Gao, Q., Gao, W., Gao, W.K., Ge, M.M., Geng, L.S., Giacinti, G., Gong, G.H., Gou, Q.B., Gu, M.H., Guo, F.L., Guo, X.L., Guo, Y.Q., Guo, Y.Y., Han, Y.A., Hasan, M., He, H.H., He, H.N., He, J.Y., He, Y., Hor, Y.K., Hou, B.W., Hou, C., Hou, X., Hu, H.B., Hu, Q., Hu, S.C., Huang, D.H., Huang, T.Q., Huang, W.J., Huang, X.T., Huang, X.Y., Huang, Y., Ji, X.L., Jia, H.Y., Jia, K., Jiang, K., Jiang, X.W., Jiang, Z.J., Jin, M., Kang, M.M., Karpikov, I., Kuleshov, D., Kurinov, K., Li, B.B., Li, C.M., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H.B., Li, H.C., Li, Jian, Li, Jie, Li, K., Li, S.D., Li, W.L., Li, X.R., Li, Xin, Li, Y.Z., Li, Zhe, Li, Zhuo, Liang, E.W., Liang, Y.F., Lin, S.J., Liu, B., Liu, C., Liu, D., Liu, D.B., Liu, H., Liu, H.D., Liu, J., Liu, J.L., Liu, M.Y., Liu, R.Y., Liu, S.M., Liu, W., Liu, Y., Liu, Y.N., Luo, Q., Luo, Y., Lv, H.K., Ma, B.Q., Ma, L.L., Ma, X.H., Mao, J.R., Min, Z., Mitthumsiri, W., Mu, H.J., Nan, Y.C., Neronov, A., Ou, L.J., Pattarakijwanich, P., Pei, Z.Y., Qi, J.C., Qi, M.Y., Qiao, B.Q., Qin, J.J., Raza, A., Ruffolo, D., Sáiz, A., Saeed, M., Semikoz, D., Shao, L., Shchegolev, O., Sheng, X.D., Shu, F.W., Song, H.C., Stenkin, Yu.V., Stepanov, V., Su, Y., Sun, D.X., Sun, Q.N., Sun, X.N., Sun, Z.B., Takata, J., Tam, P.H.T., Tang, Q.W., Tang, R., Tang, Z.B., Tian, W.W., Wang, C., Wang, C.B., Wang, G.W., Wang, H.G., Wang, H.H., Wang, J.C., Wang, Kai, Wang, L.P., Wang, L.Y., Wang, P.H., Wang, R., Wang, W., Wang, X.G., Wang, X.Y., Wang, Y., Wang, Y.D., Wang, Y.J., Wang, Z.H., Wang, Z.X., Wang, Zhen, Wang, Zheng, Wei, D.M., Wei, J.J., Wei, Y.J., Wen, T., Wu, C.Y., Wu, H.R., Wu, Q.W., Wu, S., Wu, X.F., Wu, Y.S., Xi, S.Q., Xia, J., Xiang, G.M., Xiao, D.X., Xiao, G., Xin, Y.L., Xing, Y., Xiong, D.R., Xiong, Z., Xu, D.L., Xu, R.F., Xu, R.X., Xu, W.L., Xue, L., Yan, D.H., Yan, J.Z., Yan, T., Yang, C.W., Yang, C.Y., Yang, F., Yang, F.F., Yang, L.L., Yang, M.J., Yang, R.Z., Yang, W.X., Yao, Y.H., Yao, Z.G., Yin, L.Q., Yin, N., You, X.H., You, Z.Y., Yu, Y.H., Yuan, Q., Yue, H., Zeng, H.D., Zeng, T.X., Zeng, W., Zha, M., Zhang, B.B., Zhang, F., Zhang, H., Zhang, H.M., Zhang, H.Y., Zhang, J.L., Zhang, Li, Zhang, P.F., Zhang, P.P., Zhang, R., Zhang, S.B., Zhang, S.R., Zhang, S.S., Zhang, X., Zhang, X.P., Zhang, Y.F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L.Z., Zhao, S.P., Zhao, X.H., Zheng, F., Zhong, W.J., Zhou, B., Zhou, H., Zhou, J.N., Zhou, M., Zhou, P., Zhou, R., Zhou, X.X., Zhu, B.Y., Zhu, C.G., Zhu, F.R., Zhu, H., Zhu, K.J., Zou, Y.C., and Zuo, X.
Published: 2025
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14. Flux Variations of Cosmic Ray Air Showers Detected by LHAASO-KM2A During a Thunderstorm on 10 June 2021

Author: LHAASO Collaboration, Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Zhe, Cao, Zhen, Chang, J., Chang, J. F., Chen, E. S., Chen, Liang, Chen, Long, Chen, M. J., Chen, M. L., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. J., Chen, Y., Cheng, H. L., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Duan, K. K., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Gu, F. L., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, W. H., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Li, B. B., Li, Cheng, Li, Cong, Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Long, W. J., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Min, Z., Mitthumsiri, W., Nan, Y. C., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. Y., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R., Wang, R. N., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z. H. Wang. Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., W, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yan, J. Z., Yang, C. W., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, Lu, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Y. L., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment
Abstract: The Large High Altitude Air Shower Observatory (LHAASO) has three sub-arrays, KM2A, WCDA and WFCTA. The flux variations of cosmic ray air showers were studied by analyzing the KM2A data during the thunderstorm on 10 June 2021. The number of shower events that meet the trigger conditions increases significantly in atmospheric electric fields, with maximum fractional increase of 20%. The variations of trigger rates (increases or decreases) are found to be strongly dependent on the primary zenith angle. The flux of secondary particles increases significantly, following a similar trend with that of the shower events. To better understand the observed behavior, Monte Carlo simulations are performed with CORSIKA and G4KM2A (a code based on GEANT4). We find that the experimental data (in saturated negative fields) are in good agreement with simulations, assuming the presence of a uniform upward electric field of 700 V/cm with a thickness of 1500 m in the atmosphere above the observation level. Due to the acceleration/deceleration and deflection by the atmospheric electric field, the number of secondary particles with energy above the detector threshold is modified, resulting in the changes in shower detection rate., Comment: 18 pages, 11 figures
Published: 2022
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15. Peta-electron volt gamma-ray emission from the Crab Nebula

Author: The LHAASO Collaboration, Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, H., Cai, J. T., Cao, Zhe, Chang, J., Chang, J. F., Chen, B. M., Chen, E. S., Chen, J., Chen, Liang, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Piazzoli, B. D'Ettorre, Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Dong, X. J., Duan, K. K., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, Y. L., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. C., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, Q. L., Huang, W. H., Huang, X. T., Huang, X. Y., Huang, Z. C., Ji, F., Ji, X. L., Jia, H. Y., Jiang, K., Jiang, Z. J., Jin, C., Ke, T., Kuleshov, D., Levochkin, K., Li, B. B., Li, Cheng, Li, Cong, Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, Jie, Li, Jian, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Y., Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Liu, Z. X., Long, W. J., Lu, R., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Min, Z., Mitthumsiri, W., Montaruli, T., Nan, Y. C., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. Y., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R. N., Wang, Wei, Wang, X. G., Wang, X. J., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, W. X., Wu, X. F., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xiao, H. B., Xin, G. G., Xin, Y. L., Xing, Y., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yan, J. Z., Yang, C. W., Yang, F. F., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, J. W., Zhang, L. X., Zhang, Li, Zhang, Lu, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Y. L., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The Crab pulsar and the surrounding nebula powered by the pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind is a bright source of gamma-rays carrying crucial information about this complex conglomerate. We report the detection of $\gamma$-rays with a spectrum showing gradual steepening over three energy decades, from $5\times 10^{-4}$ to $1.1$ petaelectronvolt (PeV). The ultra-high-energy photons exhibit the presence of a PeV electron accelerator (a pevatron) with an acceleration rate exceeding 15% of the absolute theoretical limit. Assuming that unpulsed $\gamma$-rays are produced at the termination of the pulsar's wind, we constrain the pevatron's size, between $0.025$ and $0.1$ pc, and the magnetic field $\approx 110 \mu$G. The production rate of PeV electrons, $2.5 \times 10^{36}$ erg $\rm s^{-1}$, constitutes 0.5% of the pulsar's spin-down luminosity, although we do not exclude a non-negligible contribution of PeV protons to the production of the highest energy $\gamma$-rays., Comment: 43 pages, 13 figures, 2 tables; Published in Science
Published: 2021
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16. Evidence for particle acceleration approaching PeV energies in the W51 complex

Author: Cao, Zhen, Aharonian, F., Axikegu, Bai, Y.X., Bao, Y.W., Bastieri, D., Bi, X.J., Bi, Y.J., Bian, W., Bukevich, A.V., Cao, Q., Cao, W.Y., Cao, Zhe, Chang, J., Chang, J.F., Chen, A.M., Chen, E.S., Chen, H.X., Chen, Liang, Chen, Lin, Chen, Long, Chen, M.J., Chen, M.L., Chen, Q.H., Chen, S., Chen, S.H., Chen, S.Z., Chen, T.L., Chen, Y., Cheng, N., Cheng, Y.D., Cui, M.Y., Cui, S.W., Cui, X.H., Cui, Y.D., Dai, B.Z., Dai, H.L., Dai, Z.G., Danzengluobu, Dong, X.Q., Duan, K.K., Fan, J.H., Fan, Y.Z., Fang, J., Fang, J.H., Fang, K., Feng, C.F., Feng, H., Feng, L., Feng, S.H., Feng, X.T., Feng, Y., Feng, Y.L., Gabici, S., Gao, B., Gao, C.D., Gao, Q., Gao, W., Gao, W.K., Ge, M.M., Geng, L.S., Giacinti, G., Gong, G.H., Gou, Q.B., Gu, M.H., Guo, F.L., Guo, X.L., Guo, Y.Q., Guo, Y.Y., Han, Y.A., Hasan, M., He, H.H., He, H.N., He, J.Y., He, Y., Hor, Y.K., Hou, B.W., Hou, C., Hou, X., Hu, H.B., Hu, Q., Hu, S.C., Huang, D.H., Huang, T.Q., Huang, W.J., Huang, X.T., Huang, X.Y., Huang, Y., Ji, X.L., Jia, H.Y., Jia, K., Jiang, K., Jiang, X.W., Jiang, Z.J., Jin, M., Kang, M.M., Karpikov, I., Kuleshov, D., Kurinov, K., Li, B.B., Li, C.M., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H.B., Li, H.C., Li, Jian, Li, Jie, Li, K., Li, S.D., Li, W.L., Li, X.R., Li, Xin, Li, Y.Z., Li, Zhe, Li, Zhuo, Liang, E.W., Liang, Y.F., Lin, S.J., Liu, B., Liu, C., Liu, D., Liu, D.B., Liu, H., Liu, H.D., Liu, J., Liu, J.L., Liu, M.Y., Liu, R.Y., Liu, S.M., Liu, W., Liu, Y., Liu, Y.N., Luo, Q., Luo, Y., Lv, H.K., Ma, B.Q., Ma, L.L., Ma, X.H., Mao, J.R., Min, Z., Mitthumsiri, W., Mu, H.J., Nan, Y.C., Neronov, A., Ou, L.J., Pattarakijwanich, P., Pei, Z.Y., Qi, J.C., Qi, M.Y., Qiao, B.Q., Qin, J.J., Raza, A., Ruffolo, D., Sáiz, A., Saeed, M., Semikoz, D., Shao, L., Shchegolev, O., Sheng, X.D., Shu, F.W., Song, H.C., Stenkin, Yu.V., Stepanov, V., Su, Y., Sun, D.X., Sun, Q.N., Sun, X.N., Sun, Z.B., Takata, J., Tam, P.H.T., Tang, Q.W., Tang, R., Tang, Z.B., Tian, W.W., Wang, C., Wang, C.B., Wang, G.W., Wang, H.G., Wang, H.H., Wang, J.C., Wang, Kai, Wang, L.P., Wang, L.Y., Wang, P.H., Wang, R., Wang, W., Wang, X.G., Wang, X.Y., Wang, Y., Wang, Y.D., Wang, Y.J., Wang, Z.H., Wang, Z.X., Wang, Zhen, Wang, Zheng, Wei, D.M., Wei, J.J., Wei, Y.J., Wen, T., Wu, C.Y., Wu, H.R., Wu, Q.W., Wu, S., Wu, X.F., Wu, Y.S., Xi, S.Q., Xia, J., Xiang, G.M., Xiao, D.X., Xiao, G., Xin, Y.L., Xing, Y., Xiong, D.R., Xiong, Z., Xu, D.L., Xu, R.F., Xu, R.X., Xu, W.L., Xue, L., Yan, D.H., Yan, J.Z., Yan, T., Yang, C.W., Yang, C.Y., Yang, F., Yang, F.F., Yang, L.L., Yang, M.J., Yang, R.Z., Yang, W.X., Yao, Y.H., Yao, Z.G., Yin, L.Q., Yin, N., You, X.H., You, Z.Y., Yu, Y.H., Yuan, Q., Yue, H., Zeng, H.D., Zeng, T.X., Zeng, W., Zha, M., Zhang, B.B., Zhang, F., Zhang, H., Zhang, H.M., Zhang, H.Y., Zhang, J.L., Zhang, Li, Zhang, P.F., Zhang, P.P., Zhang, R., Zhang, S.B., Zhang, S.R., Zhang, S.S., Zhang, X., Zhang, X.P., Zhang, Y.F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L.Z., Zhao, S.P., Zhao, X.H., Zheng, F., Zhong, W.J., Zhou, B., Zhou, H., Zhou, J.N., Zhou, M., Zhou, P., Zhou, R., Zhou, X.X., Zhu, B.Y., Zhu, C.G., Zhu, F.R., Zhu, H., Zhu, K.J., Zou, Y.C., Zuo, X., and Celli, S.
Published: 2024
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17. Calibration of the Air Shower Energy Scale of the Water and Air Cherenkov Techniques in the LHAASO experiment

Author: Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, H., Cai, J. T., Cao, Z. Cao Z., Chang, J., Chang, J. F., Chang, X. C., Chen, B. M., Chen, J., Chen, L., Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Piazzoli, B. DEttorre, Dong, X. J., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, Y. L., Gao, B., Gao, C. D., Gao, Q., Gao, W., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. C., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, Q. L., Huang, W. H., Huang, X. T., Huang, Z. C., Ji, F., Ji, X. L., Jia, H. Y., Jiang, K., Jiang, Z. J., Jin, C., Kuleshov, D., Levochkin, K., Li, B. B., Li, C., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, K., Li, W. L., Li, X., Li, X. R., Li, Y., Li, Y. Z., Li, Z., Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y. N., Liu, Z. X., Long, W. J., Lu, R., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y. C., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Ruffolo, D., Rulev, V., Saiz, A., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. R., Song, H. C., Stenkin, Yu. V., Stepanov, V., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R. N., Wang, W., Wang, X. G., Wang, X. J., Wang, X. Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z., Wang, Z. H., Wang, Z. X., Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X., Wu, X. F., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, G., Xiao, H. B., Xin, G. G., Xin, Y. L., Xing, Y., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yang, C. W., Yang, F. F., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, J. W., Zhang, L., Zhang, L. X., Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y., Zhang, Y. F., Zhang, Y. L., Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: The Wide Field-of-View Cherenkov Telescope Array (WFCTA) and the Water Cherenkov Detector Arrays (WCDA) of LHAASO are designed to work in combination for measuring the energy spectra of various cosmic ray species over a very wide energy range from a few TeV to 10 PeV. The energy calibration of WCDA can be achieved with a proven technique of measuring the westward shift of the Moon shadow of galactic cosmic rays due to the geomagnetic field. This deflection angle $\Delta$ is inversely proportional to the energy of the cosmic rays. The precise measurements of the shifts by WCDA allows us to calibrate its energy scale for energies as high as 35 TeV. The energy scale measured by WCDA can be used to cross calibrate the energy reconstructed by WFCTA, which spans the whole energy range up to 10 PeV. In this work, we will demonstrate the feasibility of the method using the data collected from April 2019 to January 2020 by the WFCTA array and WCDA-1 detector, the first of the three water Cherenkov ponds, already commissioned at LHAASO site.
Published: 2021
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18. Method to measure muon content of extensive air showers with LHAASO KM2A-WCDA synergy

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, L.X., Bai, Y.X., Bao, Y.W., Bastieri, D., Bi, X.J., Bi, Y.J., Cai, J.T., Cao, Q., Cao, W.Y., Cao, Zhe, Chang, J., Chang, J.F., Chen, E.S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M.J., Chen, M.L., Chen, Q.H., Chen, S.H., Chen, S.Z., Chen, T.L., Chen, Y., Cheng, H.L., Cheng, N., Cheng, Y.D., Cui, S.W., Cui, X.H., Cui, Y.D., Dai, B.Z., Dai, H.L., Dai, Z.G., Danzengluobu, della Volpe, D., Dong, X.Q., Duan, K.K., Fan, J.H., Fan, Y.Z., Fang, J., Fang, K., Feng, C.F., Feng, L., Feng, S.H., Feng, X.T., Feng, Y.L., Gao, B., Gao, C.D., Gao, L.Q., Gao, Q., Gao, W., Gao, W.K., Ge, M.M., Geng, L.S., Gong, G.H., Gou, Q.B., Gu, M.H., Guo, F.L., Guo, X.L., Guo, Y.Q., Guo, Y.Y., Han, Y.A., He, H.H., He, H.N., He, J.Y., He, X.B., He, Y., Heller, M., Hor, Y.K., Hou, B.W., Hou, C., Hou, X., Hu, H.B., Hu, Q., Hu, S.C., Huang, D.H., Huang, T.Q., Huang, W.J., Huang, X.T., Huang, X.Y., Huang, Y., Huang, Z.C., Ji, X.L., Jia, H.Y., Jia, K., Jiang, K., Jiang, X.W., Jiang, Z.J., Jin, M., Kang, M.M., Ke, T., Kuleshov, D., Kurinov, K., Li, B.B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H.B., Li, H.C., Li, H.Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W.L., Li, X.R., Li, Xin, Li, Y.Z., Li, Zhe, Li, Zhuo, Liang, E.W., Liang, Y.F., Lin, S.J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H.D., Liu, J., Liu, J.L., Liu, J.S., Liu, J.Y., Liu, M.Y., Liu, R.Y., Liu, S.M., Liu, W., Liu, Y., Liu, Y.N., Long, W.J., Lu, R., Luo, Q., Lv, H.K., Ma, B.Q., Ma, L.L., Ma, X.H., Mao, J.R., Min, Z., Mitthumsiri, W., Nan, Y.C., Ou, Z.W., Pang, B.Y., Pattarakijwanich, P., Pei, Z.Y., Qi, M.Y., Qi, Y.Q., Qiao, B.Q., Qin, J.J., Ruffolo, D., Sáiz, A., Shao, C.Y., Shao, L., Shchegolev, O., Sheng, X.D., Song, H.C., Stenkin, Yu.V., Stepanov, V., Su, Y., Sun, Q.N., Sun, X.N., Sun, Z.B., Tam, P.H.T., Tang, Z.B., Tian, W.W., Wang, C., Wang, C.B., Wang, G.W., Wang, H.G., Wang, H.H., Wang, J.C., Wang, J.S., Wang, K., Wang, L.P., Wang, L.Y., Wang, P.H., Wang, R., Wang, W., Wang, X.G., Wang, X.Y., Wang, Y., Wang, Y.D., Wang, Y.J., Wang, Z.H., Wang, Z.X., Wang, Zhen, Wang, Zheng, Wei, D.M., Wei, J.J., Wei, Y.J., Wen, T., Wu, C.Y., Wu, H.R., Wu, S., Wu, X.F., Wu, Y.S., Xi, S.Q., Xia, J., Xia, J.J., Xiang, G.M., Xiao, D.X., Xiao, G., Xin, G.G., Xin, Y.L., Xing, Y., Xiong, Z., Xu, D.L., Xu, R.F., Xu, R.X., Xue, L., Yan, D.H., Yan, J.Z., Yan, T., Yang, C.W., Yang, F., Yang, F.F., Yang, H.W., Yang, J.Y., Yang, L.L., Yang, M.J., Yang, R.Z., Yang, S.B., Yao, Y.H., Yao, Z.G., Ye, Y.M., Yin, L.Q., Yin, N., You, X.H., You, Z.Y., Yu, Y.H., Yuan, Q., Yue, H., Zeng, H.D., Zeng, T.X., Zeng, W., Zeng, Z.K., Zha, M., Zhang, B.B., Zhang, F., Zhang, H.M., Zhang, H.Y., Zhang, J.L., Zhang, L.X., Zhang, Li, Zhang, P.F., Zhang, P.P., Zhang, R., Zhang, S.B., Zhang, S.R., Zhang, S.S., Zhang, X., Zhang, X.P., Zhang, Y.F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L.Z., Zhao, S.P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J.N., Zhou, P., Zhou, R., Zhou, X.X., Zhu, C.G., Zhu, F.R., Zhu, H., Zhu, K.J., and Zuo, X.
Published: 2024
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19. Construction and On-site Performance of the LHAASO WFCTA Camera

Author: Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, H., Cai, J. T., Cao, Z., Chang, J., Chang, J. F., Chang, X. C., Chen, B. M., Chen, J., Chen, L., Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Piazzoli, B. D'Ettorre, Dong, X. J., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, Y. L., Gao, B., Gao, C. D., Gao, Q., Gao, W., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. C., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, Q. L., Huang, W. H., Huang, X. T., Huang, Z. C., Ji, F., Ji, X. L., Jia, H. Y., Jiang, K., Jiang, Z. J., Jin, C., Kuleshov, D., Levochkin, K., Li, B. B., Li, C., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, K., Li, W. L., Li, X., Li, X. R., Li, Y., Li, Y. Z., Li, Z., Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y. N., Liu, Z. X., Long, W. J., Lu, R., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y. C., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. R., Song, H. C., Stenkin, Yu. V., Stepanov, V., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R. N., Wang, W., Wang, X. G., Wang, X. J., Wang, X. Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z., Wang, Z. H., Wang, Z. X., Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, W. X., Wu, X. F., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, G., Xiao, H. B., Xin, G. G., Xin, Y. L., Xing, Y., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yang, C. W., Yang, F. F., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, J. W., Zhang, L., Zhang, L. X., Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y., Zhang, Y. F., Zhang, Y. L., Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Physics - Instrumentation and Detectors, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment
Abstract: The focal plane camera is the core component of the Wide Field-of-view Cherenkov/fluorescence Telescope Array (WFCTA) of the Large High-Altitude Air Shower Observatory (LHAASO). Because of the capability of working under moonlight without aging, silicon photomultipliers (SiPM) have been proven to be not only an alternative but also an improvement to conventional photomultiplier tubes (PMT) in this application. Eighteen SiPM-based cameras with square light funnels have been built for WFCTA. The telescopes have collected more than 100 million cosmic ray events and preliminary results indicate that these cameras are capable of working under moonlight. The characteristics of the light funnels and SiPMs pose challenges (e.g. dynamic range, dark count rate, assembly techniques). In this paper, we present the design features, manufacturing techniques and performances of these cameras. Finally, the test facilities, the test methods and results of SiPMs in the cameras are reported here., Comment: 45 pages, 21 figures, article
Published: 2020
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20. The observation of the Crab Nebula with LHAASO-KM2A for the performance study

Author: Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, H., Cai, J. T., Cao, Z., Chang, J., Chang, J. F., Chang, X. C., Chen, B. M., Chen, J., Chen, L., Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Piazzoli, B. D'Ettorre, Dong, X. J., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, Y. L., Gao, B., Gao, C. D., Gao, Q., Gao, W., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. C., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, Q. L., Huang, W. H., Huang, X. T., Huang, Z. C., Ji, F., Ji, X. L., Jia, H. Y., Jiang, K., Jiang, Z. J., Jin, C., Kuleshov, D., Levochkin, K., Li, B. B., Li, C., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, K., Li, W. L., Li, X., Li, X. R., Li, Y., Li, Y. Z., Li, Z., Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y. N., Liu, Z. X., Long, W. J., Lu, R., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y. C., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. R., Song, H. C., Stenkin, Yu. V., Stepanov, V., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R. N., Wang, W., Wang, X. G., Wang, X. J., Wang, X. Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z., Wang, Z. H., Wang, Z. X., Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, W. X., Wu, X. F., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, G., Xiao, H. B., Xin, G. G., Xin, Y. L., Xing, Y., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yang, C. W., Yang, F. F., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, J. W., Zhang, L., Zhang, L. X., Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y., Zhang, Y. F., Zhang, Y. L., Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: As a sub-array of the Large High Altitude Air Shower Observatory (LHAASO), KM2A is mainly designed to cover a large fraction of the northern sky to hunt for gamma-ray sources at energies above 10 TeV. Even though the detector construction is still underway, a half of the KM2A array has been operating stably since the end of 2019. In this paper, we present the pipeline of KM2A data analysis and the first observation on the Crab Nebula, a standard candle in very high energy gamma-ray astronomy. We detect gamma-ray signals from the Crab Nebula in both energy ranges of 10$-$100 TeV and $>$100 TeV with high significance, by analyzing the KM2A data of 136 live days between December 2019 and May 2020. With the observations, we test the detector performance including angular resolution, pointing accuracy and cosmic ray background rejection power. The energy spectrum of the Crab Nebula in the energy range 10-250 TeV fits well with a single power-law function dN/dE =(1.13$\pm$0.05$_{stat}$$\pm$0.08$_{sys}$)$\times$10$^{-14}$$\cdot$(E/20TeV)$^{-3.09\pm0.06_{stat}\pm0.02_{sys}}$ cm$^{-2}$ s$^{-1}$ TeV$^{-1}$. It is consistent with previous measurements by other experiments. This opens a new window of gamma-ray astronomy above 0.1 PeV through which ultrahigh-energy gamma-ray new phenomena, such as cosmic PeVatrons, might be discovered., Comment: 13 pages, 15 figures,submitted to CPC
Published: 2020
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21. Pointing calibration of LHAASO-WFCTA telescopes using bright stars

Author: Cao, Zhen, Aharonian, F., An, Q., Axikegu, Bai, Y.X., Bao, Y.W., Bastieri, D., Bi, X.J., Bi, Y.J., Cai, J.T., Cao, Q., Cao, W.Y., Cao, Zhe, Chang, J., Chang, J.F., Chen, A.M., Chen, E.S., Chen, Liang, Chen, Lin, Chen, Long, Chen, M.J., Chen, M.L., Chen, Q.H., Chen, S.H., Chen, S.Z., Chen, T.L., Chen, Y., Cheng, N., Cheng, Y.D., Cui, M.Y., Cui, S.W., Cui, X.H., Cui, Y.D., Dai, B.Z., Dai, H.L., Dai, Z.G., Danzengluobu, della Volpe, D., Dong, X.Q., Duan, K.K., Fan, J.H., Fan, Y.Z., Fang, J., Fang, K., Feng, C.F., Feng, L., Feng, S.H., Feng, X.T., Feng, Y.L., Gabici, S., Gao, B., Gao, C.D., Gao, L.Q., Gao, Q., Gao, W., Gao, W.K., Ge, M.M., Geng, L.S., Giacinti, G., Gong, G.H., Gou, Q.B., Gu, M.H., Guo, F.L., Guo, X.L., Guo, Y.Q., Guo, Y.Y., Han, Y.A., He, H.H., He, H.N., He, J.Y., He, X.B., He, Y., Heller, M., Hor, Y.K., Hou, B.W., Hou, C., Hou, X., Hu, H.B., Hu, Q., Hu, S.C., Huang, D.H., Huang, T.Q., Huang, W.J., Huang, X.T., Huang, X.Y., Huang, Y., Huang, Z.C., Ji, X.L., Jia, H.Y., Jia, K., Jiang, K., Jiang, X.W., Jiang, Z.J., Jin, M., Kang, M.M., Ke, T., Kuleshov, D., Kurinov, K., Li, B.B., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H.B., Li, H.C., Li, H.Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W.L., Li, X.R., Li, Xin, Li, Y.Z., Li, Zhe, Li, Zhuo, Liang, E.W., Liang, Y.F., Lin, S.J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H.D., Liu, J., Liu, J.L., Liu, J.Y., Liu, M.Y., Liu, R.Y., Liu, S.M., Liu, W., Liu, Y., Liu, Y.N., Lu, R., Luo, Q., Lv, H.K., Ma, B.Q., Ma, L.L., Ma, X.H., Mao, J.R., Min, Z., Mitthumsiri, W., Mu, H.J., Nan, Y.C., Neronov, A., Ou, Z.W., Pang, B.Y., Pattarakijwanich, P., Pei, Z.Y., Qi, M.Y., Qi, Y.Q., Qiao, B.Q., Qin, J.J., Ruffolo, D., Sáiz, A., Semikoz, D., Shao, C.Y., Shao, L., Shchegolev, O., Sheng, X.D., Shu, F.W., Song, H.C., Stenkin, Yu.V., Stepanov, V., Su, Y., Sun, Q.N., Sun, X.N., Sun, Z.B., Tam, P.H.T., Tang, Q.W., Tang, Z.B., Tian, W.W., Wang, C., Wang, C.B., Wang, G.W., Wang, H.G., Wang, H.H., Wang, J.C., Wang, K., Wang, L.P., Wang, L.Y., Wang, P.H., Wang, R., Wang, W., Wang, X.G., Wang, X.Y., Wang, Y., Wang, Y.D., Wang, Y.J., Wang, Z.H., Wang, Z.X., Wang, Zhen, Wang, Zheng, Wei, D.M., Wei, J.J., Wei, Y.J., Wen, T., Wu, C.Y., Wu, H.R., Wu, S., Wu, X.F., Wu, Y.S., Xi, S.Q., Xia, J., Xia, J.J., Xiang, G.M., Xiao, D.X., Xiao, G., Xin, G.G., Xin, Y.L., Xing, Y., Xiong, Z., Xu, D.L., Xu, R.F., Xu, R.X., Xu, W.L., Xue, L., Yan, D.H., Yan, J.Z., Yan, T., Yang, C.W., Yang, F., Yang, F.F., Yang, H.W., Yang, J.Y., Yang, L.L., Yang, M.J., Yang, R.Z., Yang, S.B., Yao, Y.H., Yao, Z.G., Ye, Y.M., Yin, L.Q., Yin, N., You, X.H., You, Z.Y., Yu, Y.H., Yuan, Q., Yue, H., Zeng, H.D., Zeng, T.X., Zeng, W., Zha, M., Zhang, B.B., Zhang, F., Zhang, H.M., Zhang, H.Y., Zhang, J.L., Zhang, L.X., Zhang, Li, Zhang, P.F., Zhang, P.P., Zhang, R., Zhang, S.B., Zhang, S.R., Zhang, S.S., Zhang, X., Zhang, X.P., Zhang, Y.F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L.Z., Zhao, S.P., Zheng, F., Zhou, B., Zhou, H., Zhou, J.N., Zhou, M., Zhou, P., Zhou, R., Zhou, X.X., Zhu, C.G., Zhu, F.R., Zhu, H., Zhu, K.J., and Zuo, X.
Published: 2023
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22. Reconstruction of Cherenkov image by multiple telescopes of LHAASO-WFCTA

Author: Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, J. T., Cao, Zhe, Cao, Zhen, Chang, J., Chang, J. F., Chen, E. S., Chen, Liang, Chen, Liang, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, H. L., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., D’Ettorre Piazzoli, B., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., Duan, K. K., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, X. T., Feng, Y. L., Gao, B., Gao, C. D., Gao, L. Q., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, W. H., Huang, X. T., Huang, X. Y., Huang, Y., Huang, Z. C., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, Z. J., Jin, M., Kang, M. M., Ke, T., Kuleshov, D., Levochkin, K., Li, B. B., Li, Cheng, Li, Cong, Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, Jian, Li, Jie, Li, K., Li, W. L., Li, X. R., Li, Xin, Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Long, W. J., Lu, R., Luo, Q., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Min, Z., Mitthumsiri, W., Nan, Y. C., Ou, Z. W., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Qi, Y. Q., Qiao, B. Q., Qin, J. J., Ruffolo, D., Sáiz, A., Shao, C. Y., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. Y., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R., Wang, R. N., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, G. G., Xin, Y. L., Xing, Y., Xiong, Z., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yan, J. Z., Yang, C. W., Yang, F. F., Yang, H. W., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, F., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, L. X., Zhang, Li, Zhang, Lu, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Y. L., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Published: 2022
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23. A Large Ground-Based Observing Campaign of the Disintegrating Planet K2-22b

Author: Colón, Knicole D., Zhou, George, Shporer, Avi, Collins, Karen A., Bieryla, Allyson, Espinoza, Néstor, Murgas, Felipe, Pattarakijwanich, Petchara, Awiphan, Supachai, Armstrong, James D., Bailey, Jeremy, Barentsen, Geert, Bayliss, Daniel, Chakpor, Anurak, Cochran, William D., Dhillon, Vikram S., Horne, Keith, Ireland, Michael, Kedziora-Chudczer, Lucyna, Kielkopf, John F., Komonjinda, Siramas, Latham, David W., Marsh, Tom. R., Mkrtichian, David E., Pallé, Enric, Ruffolo, David, Sefako, Ramotholo, Tinney, Chris G., Wannawichian, Suwicha, and Yuma, Suraphong
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: We present 45 ground-based photometric observations of the K2-22 system collected between December 2016 and May 2017, which we use to investigate the evolution of the transit of the disintegrating planet K2-22b. Last observed in early 2015, in these new observations we recover the transit at multiple epochs and measure a typical depth of <1.5%. We find that the distribution of our measured transit depths is comparable to the range of depths measured in observations from 2014 and 2015. These new observations also support ongoing variability in the K2-22b transit shape and time, although the overall shallowness of the transit makes a detailed analysis of these transit parameters difficult. We find no strong evidence of wavelength-dependent transit depths for epochs where we have simultaneous coverage at multiple wavelengths, although our stacked Las Cumbres Observatory data collected over days-to-months timescales are suggestive of a deeper transit at blue wavelengths. We encourage continued high-precision photometric and spectroscopic monitoring of this system in order to further constrain the evolution timescale and to aid comparative studies with the other few known disintegrating planets., Comment: Accepted for publication in the Astronomical Journal
Published: 2018
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24. Stellar and Molecular Gas Rotation in a Recently-Quenched Massive Galaxy at z~0.7

Author: Hunt, Qiana, Bezanson, Rachel, Greene, Jenny E., Spilker, Justin S., Suess, Katherine A., Kriek, Mariska, Narayanan, Desika, Feldmann, Robert, van der Wel, Arjen, and Pattarakijwanich, Petchara
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: The process by which massive galaxies transition from blue, star-forming disks into red, quiescent galaxies remains one of the most poorly-understood aspects of galaxy evolution. In this investigation, we attempt to gain a better understanding of how star formation is quenched by focusing on a massive post-starburst galaxy at z = 0.747. The target has a high stellar mass and a molecular gas fraction of ~30% -- unusually high for its low star formation rate. We look for indicators of star formation suppression mechanisms in the stellar kinematics and age distribution of the galaxy obtained from spatially resolved Gemini Integral-Field spectra and in the gas kinematics obtained from ALMA. We find evidence of significant rotation in the stars, but we do not detect a stellar age gradient within 5 kpc. The molecular gas is aligned with the stellar component, and we see no evidence of strong gas outflows. Our target may represent the product of a merger-induced starburst or of morphological quenching; however, our results are not completely consistent with any of the prominent quenching models., Comment: 8 pages, 4 figures, resubmitting to ApJL after referee report
Published: 2018
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25. Absolute calibration of LHAASO WFCTA camera based on LED

Author: Aharonian, F., An, Q., Axikegu, Bai, L.X., Bai, Y.X., Bao, Y.W., Bastieri, D., Bi, X.J., Bi, Y.J., Cai, H., Cai, J.T., Cao, Zhen, Cao, Zhe, Chang, J., Chang, J.F., Chen, B.M., Chen, E.S., Chen, J., Chen, Liang, Chen, Long, Chen, M.J., Chen, M.L., Chen, Q.H., Chen, S.H., Chen, S.Z., Chen, T.L., Chen, X.L., Chen, Y., Cheng, N., Cheng, Y.D., Cui, S.W., Cui, X.H., Cui, Y.D., Dai, B.Z., Dai, H.L., Dai, Z.G., Danzengluobu, della Volpe, D., Piazzoli, B. D’Ettorre, Dong, X.J., Duan, K.K., Fan, J.H., Fan, Y.Z., Fan, Z.X., Fang, J., Fang, K., Feng, C.F., Feng, L., Feng, S.H., Feng, Y.L., Fu, Y.T., Gan, H.Y., Gao, B., Gao, C.D., Gao, L.Q., Gao, Q., Gao, W., Ge, M.M., Geng, L.S., Gong, G.H., Gou, Q.B., Gu, M.H., Guo, F.L., Guo, J.G., Guo, X.L., Guo, Y.Q., Guo, Y.Y., Han, Y.A., He, H.H., He, H.N., He, J.C., He, S.L., He, X.B., He, Y., Heller, M., Hor, Y.K., Hou, C., Hu, H.B., Hu, S., Hu, S.C., Hu, X.J., Huang, D.H., Huang, Q.L., Huang, W.H., Huang, X.T., Huang, X.Y., Huang, Z.C., Ji, F., Ji, X.L., Jia, H.Y., Jiang, K., Jiang, Z.J., Jin, C., Ke, T., Kuleshov, D., Levochkin, K., Li, B.B., Li, Cong, Li, Cheng, Li, F., Li, H.B., Li, H.C., Li, H.Y., Li, J., Li, K., Li, W.L., Li, Xin, Li, X.R., Li, Y., Li, Y.Z., Li, Zhe, Li, Zhuo, Liang, E.W., Liang, Y.F., Lin, S.J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H.D., Liu, J., Liu, J.L., Liu, J.S., Liu, J.Y., Liu, M.Y., Liu, R.Y., Liu, S.M., Liu, W., Liu, Y., Liu, Y.N., Liu, Z.X., Long, W.J., Lu, R., Lv, H.K., Ma, B.Q., Ma, L.L., Ma, X.H., Mao, J.R., Masood, A., Min, Z., Mitthumsiri, W., Montaruli, T., Nan, Y.C., Pang, B.Y., Pattarakijwanich, P., Pei, Z.Y., Qi, M.Y., Qi, Y.Q., Qiao, B.Q., Qin, J.J., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X.D., Shi, J.Y., Song, H.C., Stenkin, Yu.V., Stepanov, V., Su, Y., Sun, Q.N., Sun, X.N., Sun, Z.B., Tam, P.H.T., Tang, Z.B., Tian, W.W., Wang, B.D., Wang, C., Wang, H., Wang, H.G., Wang, J.C., Wang, J.S., Wang, L.P., Wang, L.Y., Wang, R.N., Wang, W., Wang, X.G., Wang, X.J., Wang, X.Y., Wang, Y., Wang, Y.D., Wang, Y.J., Wang, Y.P., Wang, Z.H., Wang, Z.X., Wang, Zhen, Wang, Zheng, Wei, D.M., Wei, J.J., Wei, Y.J., Wen, T., Wu, C.Y., Wu, H.R., Wu, S., Wu, W.X., Wu, X.F., Xi, S.Q., Xia, J., Xia, J.J., Xiang, G.M., Xiao, D.X., Xiao, G., Xiao, H.B., Xin, G.G., Xin, Y.L., Xing, Y., Xu, D.L., Xu, R.X., Xue, L., Yan, D.H., Yan, J.Z., Yang, C.W., Yang, F.F., Yang, J.Y., Yang, L.L., Yang, M.J., Yang, R.Z., Yang, S.B., Yao, Y.H., Yao, Z.G., Ye, Y.M., Yin, L.Q., Yin, N., You, X.H., You, Z.Y., Yu, Y.H., Yuan, Q., Zeng, H.D., Zeng, T.X., Zeng, W., Zeng, Z.K., Zha, M., Zhai, X.X., Zhang, B.B., Zhang, H.M., Zhang, H.Y., Zhang, J.L., Zhang, J.W., Zhang, Lu, Zhang, Li, Zhang, L.X., Zhang, P.F., Zhang, P.P., Zhang, R., Zhang, S.R., Zhang, S.S., Zhang, X., Zhang, X.P., Zhang, Y.F., Zhang, Y.L., Zhang, Yong, Zhang, Yi, Zhao, B., Zhao, J., Zhao, L., Zhao, L.Z., Zhao, S.P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J.N., Zhou, P., Zhou, R., Zhou, X.X., Zhu, C.G., Zhu, F.R., Zhu, H., Zhu, K.J., and Zuo, X.
Published: 2022
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26. Line-of-shower trigger method to lower energy threshold for GRB detection using LHAASO-WCDA

Author: Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, H., Cai, J. T., Cao, Z., Cao, Z., Chang, J., Chang, J. F., Chang, X. C., Chen, B. M., Chen, J., Chen, L., Chen, L., Chen, L., Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, Volpe, D. della, Piazzoli, B. D’Ettorre, Dong, X. J., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, Y. L., Gao, B., Gao, C. D., Gao, Q., Gao, W., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. C., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, Q. L., Huang, W. H., Huang, X. T., Huang, Z. C., Ji, F., Ji, X. L., Jia, H. Y., Jiang, K., Jiang, Z. J., Jin, C., Kuleshov, D., Levochkin, K., Li, B. B., Li, C., Li, C., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, K., Li, W. L., Li, X., Li, X., Li, X. R., Li, Y., Li, Y. Z., Li, Z., Li, Z., Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y. N., Liu, Z. X., Long, W. J., Lu, R., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y. C., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. R., Song, H. C., Stenkin, Yu. V., Stepanov, V., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R. N., Wang, W., Wang, W., Wang, X. G., Wang, X. J., Wang, X. Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z., Wang, Z., Wang, Z. H., Wang, Z. X., Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, W. X., Wu, X. F., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, G., Xiao, H. B., Xin, G. G., Xin, Y. L., Xing, Y., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yang, C. W., Yang, F. F., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, J. W., Zhang, L., Zhang, L., Zhang, L. X., Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y., Zhang, Y., Zhang, Y. F., Zhang, Y. L., Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Published: 2021
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27. A dynamic range extension system for LHAASO WCDA-1

Author: Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, H., Cai, J. T., Cao, Z., Cao, Z., Chang, J., Chang, J. F., Chang, X. C., Chen, B. M., Chen, J., Chen, L., Chen, L., Chen, L., Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, Volpe, D. della, Piazzoli, B. D’Ettorre, Dong, X. J., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, Y. L., Gao, B., Gao, C. D., Gao, Q., Gao, W., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. C., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, Q. L., Huang, W. H., Huang, X. T., Huang, Y., Huang, Z. C., Ji, F., Ji, X. L., Jia, H. Y., Jiang, K., Jiang, Z. J., Jin, C., Kuleshov, D., Levochkin, K., Li, B. B., Li, C., Li, C., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, K., Li, W. L., Li, X., Li, X., Li, X. R., Li, Y., Li, Y. Z., Li, Z., Li, Z., Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y. N., Liu, Z. X., Long, W. J., Lu, R., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y. C., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. R., Song, H. C., Stenkin, Yu. V., Stepanov, V., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R. N., Wang, W., Wang, W., Wang, X. G., Wang, X. J., Wang, X. Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z., Wang, Z., Wang, Z. H., Wang, Z. X., Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, W. X., Wu, X. F., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, G., Xiao, H. B., Xin, G. G., Xin, Y. L., Xing, Y., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yang, C. W., Yang, F. F., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, J. W., Zhang, L., Zhang, L., Zhang, L. X., Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y., Zhang, Y., Zhang, Y. F., Zhang, Y. L., Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Published: 2021
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28. The ACS Fornax Cluster Survey. XII. Diffuse Star Clusters in Early-type Galaxies

Author: Liu, Yiqing, Peng, Eric W., Lim, Sungsoon, Jordán, Andrés, Blakeslee, John, Côté, Patrick, Ferrarese, Laura, and Pattarakijwanich, Petchara
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: Diffuse star clusters (DSCs) are old and dynamically hot stellar systems that have lower surface brightness and more extended morphology than globular clusters (GCs). Using the images from HST/ACS Fornax Cluster Survey, we find that 12 out of 43 early-type galaxies (ETGs) in the Fornax cluster host significant numbers of DSCs. Together with literature data from the HST/ACS Virgo Cluster Survey, where 18 out of 100 ETGs were found to host DSCs, we systematically study the relationship of DSCs with GCs, and their host galaxy environment. Two DSC hosts are post-merger galaxies, with most of the other hosts either having low mass or showing clear disk components. We find that while the number ratio of DSCs to GCs is nearly constant in massive galaxies, the DSC-to-GC ratio becomes systematically higher in lower mass hosts. This suggests that DSCs may be more efficient at forming (or surviving) in low density environments. DSC hosts are not special either in their position in the cluster, or in the galactic color-magnitude diagram. Why some disk and low-mass galaxies host DSCs while others do not is still a puzzle, however. The mean ages of DSC hosts and non-hosts are similar at similar masses, implying that formation efficiency, rather than survival, is the reason behind different DSC number fractions in early-type galaxies., Comment: 13 pages, 12 figures; accepted by ApJ
Published: 2016
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29. Performance test of the electromagnetic particle detectors for the LHAASO experiment

Author: Aharonian, F., An, Q., Axikegu, Bai, L.X., Bai, Y.X., Bao, Y.W., Bastieri, D., Bi, X.J., Bi, Y.J., Cai, H., Cai, J.T., Cao, Z., Chang, J., Chang, J.F., Chang, X.C., Chen, B.M., Chen, J., Chen, L., Chen, M.J., Chen, M.L., Chen, Q.H., Chen, S.H., Chen, S.Z., Chen, T.L., Chen, X.L., Chen, Y., Cheng, N., Cheng, Y.D., Cui, S.W., Cui, X.H., Cui, Y.D., Dai, B.Z., Dai, H.L., Dai, Z.G., Danzengluobu, della Volpe, D., D’Ettorre Piazzoli, B., Dong, X.J., Fan, J.H., Fan, Y.Z., Fan, Z.X., Fang, J., Fang, K., Feng, C.F., Feng, L., Feng, S.H., Feng, Y.L., Gao, B., Gao, C.D., Gao, Q., Gao, W., Ge, M.M., Geng, L.S., Gong, G.H., Gou, Q.B., Gu, M.H., Guo, J.G., Guo, X.L., Guo, Y.Q., Guo, Y.Y., Han, Y.A., He, H.H., He, H.N., He, J.C., He, S.L., He, X.B., He, Y., Heller, M., Hor, Y.K., Hou, C., Hou, X., Hu, H.B., Hu, S., Hu, S.C., Hu, X.J., Huang, D.H., Huang, Q.L., Huang, W.H., Huang, X.T., Huang, Z.C., Ji, F., Ji, X.L., Jia, H.Y., Jia, K., Jiang, K., Jiang, Z.J., Jin, C., Kuleshov, D., Levochkin, K., Li, B., Li, B.B., Li, C., Li, F., Li, H., Li, H.B., Li, H.C., Li, H.Y., Li, J., Li, K., Li, W.L., Li, X., Li, X.R., Li, Y., Li, Y.Z., Li, Z., Liang, E.W., Liang, Y.F., Lin, S.J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H.D., Liu, J., Liu, J.L., Liu, J.S., Liu, J.Y., Liu, M.Y., Liu, R.Y., Liu, S.M., Liu, W., Liu, Y.N., Liu, Z.X., Long, W.J., Lu, R., Lv, H.K., Ma, B.Q., Ma, L.L., Ma, X.H., Mao, J.R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y.C., Pang, B.Y., Pattarakijwanich, P., Pei, Z.Y., Qi, M.Y., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X.D., Shi, J.R., Song, H.C., Stenkin, Yu.V., Stepanov, V., Sun, Q.N., Sun, X.N., Sun, Z.B., Tam, P.H.T., Tang, Z.B., Tian, W.W., Wang, B.D., Wang, C., Wang, H., Wang, H.G., Wang, J.C., Wang, J.S., Wang, L.P., Wang, L.Y., Wang, R.N., Wang, W., Wang, X.G., Wang, X.J., Wang, X.Y., Wang, Y.D., Wang, Y.J., Wang, Y.P., Wang, Z., Wang, Z.H., Wang, Z.X., Wei, D.M., Wei, J.J., Wei, Y.J., Wen, T., Wu, C.Y., Wu, H.R., Wu, S., Wu, W.X., Wu, X.F., Xi, S.Q., Xia, J., Xia, J.J., Xiang, G.M., Xiao, G., Xiao, H.B., Xin, G.G., Xin, Y.L., Xing, Y., Xu, D.L., Xu, R.X., Xue, L., Yan, D.H., Yang, C.W., Yang, F.F., Yang, J.Y., Yang, L.L., Yang, M.J., Yang, R.Z., Yang, S.B., Yao, Y.H., Yao, Z.G., Ye, Y.M., Yin, L.Q., Yin, N., You, X.H., You, Z.Y., Yu, Y.H., Yuan, Q., Zeng, H.D., Zeng, T.X., Zeng, W., Zeng, Z.K., Zha, M., Zhai, X.X., Zhang, B.B., Zhang, H.M., Zhang, H.Y., Zhang, J.L., Zhang, J.W., Zhang, L., Zhang, L.X., Zhang, P.F., Zhang, P.P., Zhang, R., Zhang, S.R., Zhang, S.S., Zhang, X., Zhang, X.P., Zhang, Y., Zhang, Y.F., Zhang, Y.L., Zhao, B., Zhao, J., Zhao, L., Zhao, L.Z., Zhao, S.P., Zhao, X., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J.N., Zhou, P., Zhou, R., Zhou, X.X., Zhu, C.G., Zhu, F.R., Zhu, H., Zhu, K.J., and Zuo, X.
Published: 2021
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30. Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources

Author: Cao, Zhen, Aharonian, F. A., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, H., Cai, J. T., Cao, Zhe, Chang, J., Chang, J. F., Chang, X. C., Chen, B. M., Chen, J., Chen, L., Chen, Liang, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, della Volpe, D., D′Ettorre Piazzoli, B., Dong, X. J., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, Y. L., Gao, B., Gao, C. D., Gao, Q., Gao, W., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. C., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, Q. L., Huang, W. H., Huang, X. T., Huang, Z. C., Ji, F., Ji, X. L., Jia, H. Y., Jiang, K., Jiang, Z. J., Jin, C., Kuleshov, D., Levochkin, K., Li, B. B., Li, Cong, Li, Cheng, Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, K., Li, W. L., Li, X., Li, Xin, Li, X. R., Li, Y., Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y. N., Liu, Z. X., Long, W. J., Lu, R., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y. C., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. R., Song, H. C., Stenkin, Yu. V., Stepanov, V., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R. N., Wang, W., Wang, W., Wang, X. G., Wang, X. J., Wang, X. Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Zheng, Wang, Zhen, Wang, Z. H., Wang, Z. X., Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, W. X., Wu, X. F., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, G., Xiao, H. B., Xin, G. G., Xin, Y. L., Xing, Y., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yang, C. W., Yang, F. F., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, J. W., Zhang, L., Zhang, Li, Zhang, L. X., Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Yong, Zhang, Yi, Zhang, Y. F., Zhang, Y. L., Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Published: 2021
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31. The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III

Author: Alam, Shadab, Albareti, Franco D., Prieto, Carlos Allende, Anders, F., Anderson, Scott F., Andrews, Brett H., Armengaud, Eric, Aubourg, Éric, Bailey, Stephen, Bautista, Julian E., Beaton, Rachael L., Beers, Timothy C., Bender, Chad F., Berlind, Andreas A., Beutler, Florian, Bhardwaj, Vaishali, Bird, Jonathan C., Bizyaev, Dmitry, Blake, Cullen H., Blanton, Michael R., Blomqvist, Michael, Bochanski, John J., Bolton, Adam S., Bovy, Jo, Bradley, A. Shelden, Brandt, W. N., Brauer, D. E., Brinkmann, J., Brown, Peter J., Brownstein, Joel R., Burden, Angela, Burtin, Etienne, Busca, Nicolás G., Cai, Zheng, Capozzi, Diego, Rosell, Aurelio Carnero, Carrera, Ricardo, Chen, Yen-Chi, Chiappini, Cristina, Chojnowski, S. Drew, Chuang, Chia-Hsun, Clerc, Nicolas, Comparat, Johan, Covey, Kevin, Croft, Rupert A. C., Cuesta, Antonio J., Cunha, Katia, da Costa, Luiz N., Da Rio, Nicola, Davenport, James R. A., Dawson, Kyle S., De Lee, Nathan, Delubac, Timothée, Deshpande, Rohit, Dutra-Ferreira, Letícia, Dwelly, Tom, Ealet, Anne, Ebelke, Garrett L., Edmondson, Edward M., Eisenstein, Daniel J., Escoffier, Stephanie, Esposito, Massimiliano, Fan, Xiaohui, Fernández-Alvar, Emma, Feuillet, Diane, Ak, Nurten Filiz, Finley, Hayley, Finoguenov, Alexis, Flaherty, Kevin, Fleming, Scott W., Font-Ribera, Andreu, Foster, Jonathan, Frinchaboy, Peter M., Galbraith-Frew, J. G., García-Hernández, D. A., Pérez, Ana E. García, Gaulme, Patrick, Ge, Jian, Génova-Santos, R., Ghezzi, Luan, Gillespie, Bruce A., Girardi, Léo, Goddard, Daniel, Gontcho, Satya Gontcho A, Hernández, Jonay I. González, Grebel, Eva K., Grieb, Jan Niklas, Grieves, Nolan, Gunn, James E., Guo, Hong, Harding, Paul, Hasselquist, Sten, Hawley, Suzanne L., Hayden, Michael, Hearty, Fred R., Ho, Shirley, Hogg, David W., Holley-Bockelmann, Kelly, Holtzman, Jon A., Honscheid, Klaus, Huehnerhoff, Joseph, Jiang, Linhua, Johnson, Jennifer A., Kinemuchi, Karen, Kirkby, David, Kitaura, Francisco, Klaene, Mark A., Kneib, Jean-Paul, Koenig, Xavier P., Lam, Charles R., Lan, Ting-Wen, Lang, Dustin, Laurent, Pierre, Goff, Jean-Marc Le, Leauthaud, Alexie, Lee, Khee-Gan, Lee, Young Sun, Licquia, Timothy C., Liu, Jian, Long, Daniel C., López-Corredoira, Martín, Lorenzo-Oliveira, Diego, Lucatello, Sara, Lundgren, Britt, Lupton, Robert H., Mack III, Claude E., Mahadevan, Suvrath, Maia, Marcio A. G., Majewski, Steven R., Malanushenko, Elena, Malanushenko, Viktor, Manchado, A., Manera, Marc, Mao, Qingqing, Maraston, Claudia, Marchwinski, Robert C., Margala, Daniel, Martell, Sarah L., Martig, Marie, Masters, Karen L., McBride, Cameron K., McGehee, Peregrine M., McGreer, Ian D., McMahon, Richard G., Ménard, Brice, Menzel, Marie-Luise, Merloni, Andrea, Mészáros, Szabolcs, Miller, Adam A., Miralda-Escudé, Jordi, Miyatake, Hironao, Montero-Dorta, Antonio D., More, Surhud, Morice-Atkinson, Xan, Morrison, Heather L., Muna, Demitri, Myers, Adam D., Newman, Jeffrey A., Neyrinck, Mark, Nguyen, Duy Cuong, Nichol, Robert C., Nidever, David L., Noterdaeme, Pasquier, Nuza, Sebastián E., O'Connell, Julia E., O'Connell, Robert W., O'Connell, Ross, Ogando, Ricardo L. C., Olmstead, Matthew D., Oravetz, Audrey E., Oravetz, Daniel J., Osumi, Keisuke, Owen, Russell, Padgett, Deborah L., Padmanabhan, Nikhil, Paegert, Martin, Palanque-Delabrouille, Nathalie, Pan, Kaike, Parejko, John K., Park, Changbom, Pâris, Isabelle, Pattarakijwanich, Petchara, Pellejero-Ibanez, M., Pepper, Joshua, Percival, Will J., Pérez-Fournon, Ismael, Pérez-Ràfols, Ignasi, Petitjean, Patrick, Pieri, Matthew M., Pinsonneault, Marc H., de Mello, Gustavo F. Porto, Prada, Francisco, Prakash, Abhishek, Price-Whelan, Adrian M., Raddick, M. Jordan, Rahman, Mubdi, Reid, Beth A., Rich, James, Rix, Hans-Walter, Robin, Annie C., Rockosi, Constance M., Rodrigues, Thaíse S., Rodríguez-Rottes, Sergio, Roe, Natalie A., Ross, Ashley J., Ross, Nicholas P., Rossi, Graziano, Ruan, John J., Rubiño-Martín, J. A., Rykoff, Eli S., Salazar-Albornoz, Salvador, Salvato, Mara, Samushia, Lado, Sánchez, Ariel G., Santiago, Basílio, Sayres, Conor, Schiavon, Ricardo P., Schlegel, David J., Schmidt, Sarah J., Schneider, Donald P., Schultheis, Mathias, Schwope, Axel D., Scóccola, C. G., Sellgren, Kris, Seo, Hee-Jong, Shane, Neville, Shen, Yue, Shetrone, Matthew, Shu, Yiping, Sivarani, Thirupathi, Skrutskie, M. F., Slosar, Anže, Smith, Verne V., Sobreira, Flávia, Stassun, Keivan G., Steinmetz, Matthias, Strauss, Michael A., Streblyanska, Alina, Swanson, Molly E. C., Tan, Jonathan C., Tayar, Jamie, Terrien, Ryan C., Thakar, Aniruddha R., Thomas, Daniel, Thompson, Benjamin A., Tinker, Jeremy L., Tojeiro, Rita, Troup, Nicholas W., Vargas-Magaña, Mariana, Vazquez, Jose A., Verde, Licia, Viel, Matteo, Vogt, Nicole P., Wake, David A., Wang, Ji, Weaver, Benjamin A., Weinberg, David H., Weiner, Benjamin J., White, Martin, Wilson, John C., Wisniewski, John P., Wood-Vasey, W. M., Yèche, Christophe, York, Donald G., Zakamska, Nadia L., Zamora, O., Zasowski, Gail, Zehavi, Idit, Zhao, Gong-Bo, Zheng, Zheng, Zhou, Xu, Zhou, Zhimin, Zhu, Guangtun, and Zou, Hu
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics
Abstract: The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 sq. deg of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-Object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include measured abundances of 15 different elements for each star. In total, SDSS-III added 2350 sq. deg of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 sq. deg; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5,513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra., Comment: DR12 data are available at http://www.sdss3.org/dr12. 30 pages. 11 figures. Accepted to ApJS
Published: 2015
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32. Dust Content, Galaxy Orientations, and Shape Noise in Imaging Surveys

Author: Pattarakijwanich, Petchara and Schmidt, Fabian
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We show that dust absorption in disk galaxies leads to a color- and orientation-dependent centroid shift which is expected to be observable in multi-band imaging surveys. This centroid shift is an interesting new probe which contains astrophysically and cosmologically relevant information: it can be used to probe the dust content of a large sample of galaxies, and to reduce the shape noise due to inclination of disk galaxies for weak lensing shear. Specifically, we find that data sets comparable to CFHTLenS, the Dark Energy Survey (DES) or the Hyper Suprime-Cam (HSC) survey should provide a dust measurement for several hundred galaxies per square degree. Conversely, given knowledge of the dust optical depth, this technique will significantly lower the shape noise for the brightest galaxies in the sample (signal-to-noise greater than a few hundred), thereby increasing their relative importance for the weak lensing shear measurement., Comment: 14 pages, 10 figures, published in Astrophysical Journal
Published: 2014

33. The Evolution of Post-Starburst Galaxies from $z\sim1$ to the Present

Author: Pattarakijwanich, Petchara, Strauss, Michael A., Ho, Shirley, and Ross, Nicholas P.
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: Post-starburst galaxies are in the transitional stage between blue, star-forming galaxies and red, quiescent galaxies, and therefore hold important clues for our understanding of galaxy evolution. In this paper, we systematically searched for and identified a large sample of post-starburst galaxies from the spectroscopic dataset of the Sloan Digital Sky Survey (SDSS) Data Release 9. In total, we found more than 6000 objects with redshifts between $z\sim0.05$ and $z\sim1.3$, making this the largest sample of post-starburst galaxies in the literature. We calculated the luminosity function of the post-starburst galaxies using two uniformly selected subsamples: the SDSS Main Galaxy Sample and the Baryon Oscillation Spectroscopic Survey CMASS Sample. The luminosity functions are reasonably fit by half-Gaussian functions. The peak magnitudes shift as a function of redshift from $M\sim-23.5$ at $z\sim0.8$ to $M\sim-20.3$ at $z\sim0.1$. This is consistent with the downsizing trend, whereby more massive galaxies form earlier than low-mass galaxies. We compared the mass of the post-starburst stellar population found in our sample to the decline of the global star-formation rate and found that only a small amount ($\sim1\%$) of all star-formation quenching in the redshift range $z=0.2-0.7$ results in post-starburst galaxies in the luminosity range our sample is sensitive to. Therefore, luminous post-starburst galaxies are not the place where most of the decline in star-formation rate of the universe is happening., Comment: 26 pages, 24 figures, 8 tables. Accepted for publication in The Astrophysical Journal
Published: 2014
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34. Near Infrared Spectra and Intrinsic Luminosities of Candidate Type II Quasars at 2 < z < 3.4

Author: Greene, Jenny E, Alexandroff, Rachael, Strauss, Michael A, Zakamska, Nadia L, Lang, Dustin, Liu, Guilin, Pattarakijwanich, Petchara, Hamann, Frederick, Ross, Nicholas P, Myers, Adam D, Brandt, W Niel, York, Donald, and Schneider, Donald P
Subjects: Astrophysics - Astrophysics of Galaxies, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present JHK near-infrared (NIR) spectroscopy of 25 candidate Type II quasars selected from the Sloan Digital Sky Survey, using Triplespec on the Apache Point Observatory 3.5m telescope, FIRE at the Magellan/Baade 6.5m telescope, and GNIRS on Gemini. At redshifts of 2 < z < 3.4, our NIR spectra probe the rest-frame optical region of these targets, which were initially selected to have strong lines of CIV and Ly alpha, with FWHM<2000 km/s from the SDSS pipeline. We use the [OIII]5007 line shape as a model for the narrow line region emission, and find that \halpha\ consistently requires a broad component with FWHMs ranging from 1000 to 7500 km/s. Interestingly, the CIV lines also require broad bases, but with considerably narrower widths of 1000 to 4500 km/s. Estimating the extinction using the Balmer decrement and also the relationship in lower-z quasars between rest equivalent width and luminosity in the [OIII] line, we find typical A_V values of 0-2 mag, which naturally explain the attenuated CIV lines relative to Halpha. We propose that our targets are moderately obscured quasars. We also describe one unusual object with three distinct velocity peaks in its [OIII] spectrum., Comment: Accepted for publication in ApJ, 18 pages, 14 figures
Published: 2014
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35. Discovery of Four High Proper Motion L Dwarfs, Including a 10 pc L Dwarf at the L/T Transition

Author: Castro, Philip J., Gizis, John E., Harris, Hugh C., Mace, Gregory N., Kirkpatrick, J. Davy, McLean, Ian S., Pattarakijwanich, Petchara, and Skrutskie, Michael F.
Subjects: Astrophysics - Solar and Stellar Astrophysics
Abstract: We discover four high proper motion L dwarfs by comparing the Wide-field Infrared Survey Explorer (WISE) to the Two Micron All Sky Survey (2MASS). WISE J140533.32+835030.5 is an L dwarf at the L/T transition with a proper motion of 0.85+/-0.02" yr^-1, previously overlooked due to its proximity to a bright star (V=12 mag). From optical spectroscopy we find a spectral type of L8, and from moderate-resolution J band spectroscopy we find a near-infrared spectral type of L9. We find WISE J140533.32+835030.5 to have a distance of 9.7+/-1.7 pc, bringing the number of L dwarfs at the L/T transition within 10 pc from six to seven. WISE J040137.21+284951.7, WISE J040418.01+412735.6, and WISE J062442.37+662625.6 are all early L dwarfs within 25 pc, and were classified using optical and low-resolution near-infrared spectra. WISE J040418.01+412735.6 is an L2 pec (red) dwarf, a member of the class of unusually red L dwarfs. We use follow-up optical and low-resolution near-infrared spectroscopy to classify a previously discovered (Castro & Gizis 2012) fifth object WISEP J060738.65+242953.4 as an (L8 Opt/L9 NIR), confirming it as an L dwarf at the L/T transition within 10 pc. WISEP J060738.65+242953.4 shows tentative CH_4 in the H band, possibly the result of unresolved binarity with an early T dwarf, a scenario not supported by binary spectral template fitting. If WISEP J060738.65+242953.4 is a single object, it represents the earliest onset of CH_4 in the H band of an L/T transition dwarf in the SpeX Library. As very late L dwarfs within 10 pc, WISE J140533.32+835030.5 and WISEP J060738.65+242953.4 will play a vital role in resolving outstanding issues at the L/T transition., Comment: 45 pages, 12 figures, accepted for publication in ApJ
Published: 2013
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36. SDSS 0956+5128: A Broad-line Quasar with Extreme Velocity Offsets

Author: Steinhardt, Charles L., Schramm, Malte, Silverman, John D., Alexandroff, Rachael, Capak, Peter, Civano, Francesca, Elvis, Martin, Masters, Dan, Mobasher, Bahram, Pattarakijwanich, Petchara, and Strauss, Michael A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We report on the discovery of a Type 1 quasar, SDSS 0956+5128, with a surprising combination of extreme velocity offsets. SDSS 0956+5128 is a broad-lined quasar exhibiting emission lines at three substantially different redshifts: a systemic redshift of z ~ 0.714 based on narrow emission lines, a broad MgII emission line centered 1200 km/s bluer than the systemic velocity, at z ~ 0.707, and broad H\alpha and H\beta emission lines centered at z ~ 0.690. The Balmer line peaks are 4100 km/s bluer than the systemic redshift. There are no previously known objects with such an extreme difference between broad MgII and broad Balmer emission. The two most promising explanations are either an extreme disk emitter or a high-velocity black hole recoil. However, neither explanation appears able to explain all of the observed features of SDSS 0956+5128, so the object may provide a challenge to our general understanding of quasar physics., Comment: ApJ, accepted
Published: 2012
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37. The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey

Author: Collaboration, SDSS-III, Ahn, Christopher P., Alexandroff, Rachael, Prieto, Carlos Allende, Anderson, Scott F., Anderton, Timothy, Andrews, Brett H., Bailey, Éric Aubourg Stephen, Barnes, Rory, Bautista, Julian, Beers, Timothy C., Beifiori, Alessandra, Berlind, Andreas A., Bhardwaj, Vaishali, Bizyaev, Dmitry, Blake, Cullen H., Blanton, Michael R., Blomqvist, Michael, Bochanski, John J., Bolton, Adam S., Borde, Arnaud, Bovy, Jo, Brandt, W. N., Brinkmann, J., Brown, Peter J., Brownstein, Joel R., Bundy, Kevin, Busca, N. G., Carithers, William, Carnero, Aurelio R., Carr, Michael A., Casetti-Dinescu, Dana I., Chen, Yanmei, Chiappini, Cristina, Comparat, Johan, Connolly, Natalia, Crepp, Justin R., Cristiani, Stefano, Croft, Rupert A. C., Cuesta, Antonio J., da Costa, Luiz N., Davenport, James R. A., Dawson, Kyle S., de Putter, Roland, De Lee, Nathan, Delubac, Timothée, Dhital, Saurav, Ealet, Anne, Ebelke, Garrett L., Edmondson, Edward M., Eisenstein, Daniel J., Escoffier, S., Esposito, Massimiliano, Evans, Michael L., Fan, Xiaohui, Castellá, Bruno Femení a, Alvar, Emma Fernández, Ferreira, Leticia D., Ak, N. Filiz, Finley, Hayley, Fleming, Scott W., Font-Ribera, Andreu, Frinchaboy, Peter M., García-Hernández, D. A., Pérez, A. E. García, Ge, Jian, Génova-Santos, R., Gillespie, Bruce A., Girardi, Léo, Hernández, Jonay I. González, Grebel, Eva K., Gunn, James E., Haggard, Daryl, Hamilton, Jean-Christophe, Harris, David W., Hawley, Suzanne L., Hearty, Frederick R., Ho, Shirley, Hogg, David W., Holtzman, Jon A., Honscheid, Klaus, Huehnerhoff, J., Ivans, Inese I., Ivezić, Zeljko, Jacobson, Heather R., Jiang, Linhua, Johansson, Jonas, Johnson, Jennifer A., Kauffmann, Guinevere, Kirkby, David, Kirkpatrick, Jessica A., Klaene, Mark A., Knapp, Gillian R., Kneib, Jean-Paul, Goff, Jean-Marc Le, Leauthaud, Alexie, Lee, Khee-Gan, Lee, Young Sun, Long, Daniel C., Loomis, Craig P., Lucatello, Sara, Lundgren, Britt, Lupton, Robert H., Ma, Bo, Ma, Zhibo, MacDonald, Nicholas, Mahadevan, Suvrath, Maia, Marcio A. G., Majewski, Steven R., Makler, Martin, Malanushenko, Elena, Malanushenko, Viktor, Manchado, A., Mandelbaum, Rachel, Manera, Marc, Maraston, Claudia, Margala, Daniel, Martell, Sarah L., McBride, Cameron K., McGreer, Ian D., McMahon, Richard G., Ménard, Brice, Meszaros, Sz., Miralda-Escudé, Jordi, Montero-Dorta, Antonio D., Montesano, Francesco, Morrison, Heather L., Muna, Demitri, Munn, Jeffrey A., Murayama, Hitoshi, Myers, Adam D., Neto, A. F., Nguyen, Duy Cuong, Nichol, Robert C., Nidever, David L., Noterdaeme, Pasquier, Ogando, Ricardo L. C., Olmstead, Matthew D., Oravetz, Daniel J., Owen, Russell, Padmanabhan, Nikhil, Palanque-Delabrouille, Nathalie, Pan, Kaike, Parejko, John K., Parihar, Prachi, Pâris, Isabelle, Pattarakijwanich, Petchara, Pepper, Joshua, Percival, Will J., Pérez-Fournon, Ismael, Pérez-Ráfols, Ignasi, Petitjean, Patrick, Pforr, Janine, Pieri, Matthew M., Pinsonneault, Marc H., de Mello, G. F. Porto, Prada, Francisco, Price-Whelan, Adrian M., Raddick, M. Jordan, Rebolo, Rafael, Rich, James, Richards, Gordon T., Robin, Annie C., Rocha-Pinto, Helio J., Rockosi, Constance M., Roe, Natalie A., Ross, Ashley J., Ross, Nicholas P., Rubiño-Martin, J. A., Samushia, Lado, Almeida, J. Sanchez, Sánchez, Ariel G., Santiago, Basílio, Sayres, Conor, Schlegel, David J., Schlesinger, Katharine J., Schmidt, Sarah J., Schneider, Donald P., Schwope, Axel D., Scóccola, C. G., Seljak, Uros, Sheldon, Erin, Shen, Yue, Shu, Yiping, Simmerer, Jennifer, Simmons, Audrey E., Skibba, Ramin A., Slosar, A., Sobreira, Flavia, Sobeck, Jennifer S., Stassun, Keivan G., Steele, Oliver, Steinmetz, Matthias, Strauss, Michael A., Swanson, Molly E. C., Tal, Tomer, Thakar, Aniruddha R., Thomas, Daniel, Thompson, Benjamin A., Tinker, Jeremy L., Tojeiro, Rita, Tremonti, Christy A., Magaña, M. Vargas, Verde, Licia, Viel, Matteo, Vikas, Shailendra K., Vogt, Nicole P., Wake, David A., Wang, Ji, Weaver, Benjamin A., Weinberg, David H., Weiner, Benjamin J., West, Andrew A., White, Martin, Wilson, John C., Wisniewski, John P., Wood-Vasey, W. M., Yanny, Brian, Yèche, Christophe, York, Donald G., Zamora, O., Zasowski, Gail, Zehavi, Idit, Zhao, Gong-Bo, Zheng, Zheng, Zhu, Guangtun, and Zinn, Joel C.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar spectra, along with the data presented in previous data releases. These spectra were obtained with the new BOSS spectrograph and were taken between 2009 December and 2011 July. In addition, the stellar parameters pipeline, which determines radial velocities, surface temperatures, surface gravities, and metallicities of stars, has been updated and refined with improvements in temperature estimates for stars with T_eff<5000 K and in metallicity estimates for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars presented in DR8, including stars from SDSS-I and II, as well as those observed as part of the SDSS-III Sloan Extension for Galactic Understanding and Exploration-2 (SEGUE-2). The astrometry error introduced in the DR8 imaging catalogs has been corrected in the DR9 data products. The next data release for SDSS-III will be in Summer 2013, which will present the first data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) along with another year of data from BOSS, followed by the final SDSS-III data release in December 2014., Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at http://www.sdss3.org/dr9
Published: 2012
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38. Construction and on-site performance of the LHAASO WFCTA camera

Author: Aharonian, F., An, Q., Axikegu, Bai, L. X., Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Cai, H., Cai, J. T., Cao, Z., Cao, Z., Chang, J., Chang, J. F., Chang, X. C., Chen, B. M., Chen, J., Chen, L., Chen, L., Chen, L., Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, X. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, Volpe, D. della, Piazzoli, B. D’Ettorre, Dong, X. J., Fan, J. H., Fan, Y. Z., Fan, Z. X., Fang, J., Fang, K., Feng, C. F., Feng, L., Feng, S. H., Feng, Y. L., Gao, B., Gao, C. D., Gao, Q., Gao, W., Ge, M. M., Geng, L. S., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, J. G., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., He, H. H., He, H. N., He, J. C., He, S. L., He, X. B., He, Y., Heller, M., Hor, Y. K., Hou, C., Hou, X., Hu, H. B., Hu, S., Hu, S. C., Hu, X. J., Huang, D. H., Huang, Q. L., Huang, W. H., Huang, X. T., Huang, Z. C., Ji, F., Ji, X. L., Jia, H. Y., Jiang, K., Jiang, Z. J., Jin, C., Kuleshov, D., Levochkin, K., Li, B. B., Li, C., Li, C., Li, F., Li, H. B., Li, H. C., Li, H. Y., Li, J., Li, K., Li, W. L., Li, X., Li, X., Li, X. R., Li, Y., Li, Y. Z., Li, Z., Li, Z., Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, J. S., Liu, J. Y., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y. N., Liu, Z. X., Long, W. J., Lu, R., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y. C., Pang, B. Y., Pattarakijwanich, P., Pei, Z. Y., Qi, M. Y., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X. D., Shi, J. R., Song, H. C., Stenkin, Yu. V., Stepanov, V., Sun, Q. N., Sun, X. N., Sun, Z. B., Tam, P. H. T., Tang, Z. B., Tian, W. W., Wang, B. D., Wang, C., Wang, H., Wang, H. G., Wang, J. C., Wang, J. S., Wang, L. P., Wang, L. Y., Wang, R. N., Wang, W., Wang, W., Wang, X. G., Wang, X. J., Wang, X. Y., Wang, Y. D., Wang, Y. J., Wang, Y. P., Wang, Z., Wang, Z., Wang, Z. H., Wang, Z. X., Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, S., Wu, W. X., Wu, X. F., Xi, S. Q., Xia, J., Xia, J. J., Xiang, G. M., Xiao, G., Xiao, H. B., Xin, G. G., Xin, Y. L., Xing, Y., Xu, D. L., Xu, R. X., Xue, L., Yan, D. H., Yang, C. W., Yang, F. F., Yang, J. Y., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, S. B., Yao, Y. H., Yao, Z. G., Ye, Y. M., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Zeng, H. D., Zeng, T. X., Zeng, W., Zeng, Z. K., Zha, M., Zhai, X. X., Zhang, B. B., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, J. W., Zhang, L., Zhang, L., Zhang, L. X., Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. R., Zhang, S S., Zhang, X., Zhang, X. P., Zhang, Y., Zhang, Y., Zhang, Y. F., Zhang, Y. L., Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J. N., Zhou, P., Zhou, R., Zhou, X. X., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., and Zuo, X.
Published: 2021
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39. Analysis of Moon shadow from 2021-2022 LHAASO WCDA Data.

Author: Maburee, J, Mitthumsiri, W, Nuntiyakul, W, Pattarakijwanich, P, Ruffolo, D, Sáiz, A, and Seripienlert, A
Published: 2023
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40. Flux variations of cosmic ray air showers detected by LHAASO-KM2A during a thunderstorm on June 10, 2021*

Author: Aharonian, F., primary, An, Q., additional, Bai, L.X., additional, Bai, Y.X., additional, Bao, Y.W., additional, Bastieri, D., additional, Bi, X.J., additional, Bi, Y.J., additional, Cai, J.T., additional, Cao, Zhe, additional, Cao, Zhen, additional, Chang, J., additional, Chang, J.F., additional, Chen, E.S., additional, Chen, Liang, additional, Chen, Long, additional, Chen, M.J., additional, Chen, M.L., additional, Chen, S.H., additional, Chen, S.Z., additional, Chen, T.L., additional, Chen, X. J., additional, Chen, Y., additional, Cheng, H.L., additional, Cheng, N., additional, Cheng, Y.D., additional, Cui, S.W., additional, Cui, X.H., additional, Cui, Y.D., additional, Dai, B.Z., additional, Dai, H.L., additional, Dai, Z.G., additional, Volpe, D. della, additional, Duan, K.K., additional, Fan, J.H., additional, Fan, Y.Z., additional, Fan, Z.X., additional, Fang, J., additional, Fang, K., additional, Feng, C.F., additional, Feng, L., additional, Feng, S.H., additional, Feng, X.T., additional, Feng, Y.L., additional, Gao, B., additional, Gao, C.D., additional, Gao, L.Q., additional, Gao, Q., additional, Gao, W., additional, Gao, W.K., additional, Ge, M.M., additional, Geng, L.S., additional, Gong, G.H., additional, Gou, Q.B., additional, Gu, M.H., additional, Guo, F.L., additional, Guo, J.G., additional, Guo, X.L., additional, Guo, Y.Q., additional, Guo, Y.Y., additional, Han, Y.A., additional, He, H.H., additional, He, H.N., additional, He, S.L., additional, He, X.B., additional, He, Y., additional, Heller, M., additional, Hor, Y.K., additional, Hou, C., additional, Hou, X., additional, Hu, H.B., additional, Hu, Q., additional, Hu, S., additional, Hu, S.C., additional, Hu, X.J., additional, Huang, D.H., additional, Huang, W.H., additional, Huang, X.T., additional, Huang, X.Y., additional, Huang, Y., additional, Huang, Z.C., additional, Ji, X.L., additional, Jia, H.Y., additional, Jia, K., additional, Jiang, K., additional, Jiang, Z.J., additional, Jin, M., additional, Kang, M.M., additional, Ke, T., additional, Kuleshov, D., additional, Li, B.B., additional, Li, Cheng, additional, Li, Cong, additional, Li, F., additional, Li, H.B., additional, Li, H.C., additional, Li, H.Y., additional, Li, J., additional, Li, Jian, additional, Li, Jie, additional, Li, K., additional, Li, W.L., additional, Li, X.R., additional, Li, Xin, additional, Li, Y.Z., additional, Li, Zhe, additional, Li, Zhuo, additional, Liang, E.W., additional, Liang, Y.F., additional, Lin, S.J., additional, Liu, B., additional, Liu, C., additional, Liu, D., additional, Liu, H., additional, Liu, H.D., additional, Liu, J., additional, Liu, J.L., additional, Liu, J.S., additional, Liu, J.Y., additional, Liu, M.Y., additional, Liu, R.Y., additional, Liu, S.M., additional, Liu, W., additional, Liu, Y., additional, Liu, Y.N., additional, Long, W.J., additional, Lu, R., additional, Luo, Q., additional, Lv, H.K., additional, Ma, B.Q., additional, Ma, L.L., additional, Ma, X.H., additional, Mao, J.R., additional, Masood, A., additional, Min, Z., additional, Mitthumsiri, W., additional, Nan, Y.C., additional, Ou, Z.W., additional, Pang, B.Y., additional, Pattarakijwanich, P., additional, Pei, Z.Y., additional, Qi, M.Y., additional, Qi, Y.Q., additional, Qiao, B.Q., additional, Qin, J.J., additional, Ruffolo, D., additional, Sáiz, A., additional, Shao, C.Y., additional, Shao, L., additional, Shchegolev, O., additional, Sheng, X.D., additional, Shi, J.Y., additional, Song, H.C., additional, Stenkin, Yu.V., additional, Stepanov, V., additional, Su, Y., additional, Sun, Q.N., additional, Sun, X.N., additional, Sun, Z.B., additional, Tam, P.H.T., additional, Tang, Z.B., additional, Tian, W.W., additional, Wang, B.D., additional, Wang, C., additional, Wang, H., additional, Wang, H.G., additional, Wang, J.C., additional, Wang, J.S., additional, Wang, L.P., additional, Wang, L.Y., additional, Wang, R., additional, Wang, R.N., additional, Wang, W., additional, Wang, X.G., additional, Wang, X.Y., additional, Wang, Y., additional, Wang, Y.D., additional, Wang, Y.J., additional, Wang, Y.P., additional, Wang, Z.H., additional, Wang, Z.X., additional, Wang, Zhen, additional, Wang, Zheng, additional, Wei, D.M., additional, Wei, J.J., additional, Wei, Y.J., additional, Wen, T., additional, Wu, C.Y., additional, Wu, H.R., additional, Wu, S., additional, Wu, X.F., additional, Wu, Y.S., additional, Xi, S.Q., additional, Xia, J., additional, Xia, J.J., additional, Xiang, G.M., additional, Xiao, D.X., additional, Xiao, G., additional, Xin, G.G., additional, Xin, Y.L., additional, Xing, Y., additional, Xiong, Z., additional, Xu, D.L., additional, Xu, R.X., additional, Xue, L., additional, Yan, D.H., additional, Yan, J.Z., additional, Yang, C.W., additional, Yang, F.F., additional, Yang, H.W., additional, Yang, J.Y., additional, Yang, L.L., additional, Yang, M.J., additional, Yang, R.Z., additional, Yang, S.B., additional, Yao, Y.H., additional, Yao, Z.G., additional, Ye, Y.M., additional, Yin, L.Q., additional, Yin, N., additional, You, X.H., additional, You, Z.Y., additional, Yu, Y.H., additional, Yuan, Q., additional, Yue, H., additional, Zeng, H.D., additional, Zeng, T.X., additional, Zeng, W., additional, Zeng, Z.K., additional, Zha, M., additional, Zhai, X.X., additional, Zhang, B.B., additional, Zhang, F., additional, Zhang, H.M., additional, Zhang, H.Y., additional, Zhang, J.L., additional, Zhang, L.X., additional, Zhang, Li, additional, Zhang, Lu, additional, Zhang, P.F., additional, Zhang, P.P., additional, Zhang, R., additional, Zhang, S.B., additional, Zhang, S.R., additional, Zhang, S.S., additional, Zhang, X., additional, Zhang, X.P., additional, Zhang, Y.F., additional, Zhang, Y.L., additional, Zhang, Yi, additional, Zhang, Yong, additional, Zhao, B., additional, Zhao, J., additional, Zhao, L., additional, Zhao, L.Z., additional, Zhao, S.P., additional, Zheng, F., additional, Zheng, Y., additional, Zhou, B., additional, Zhou, H., additional, Zhou, J.N., additional, Zhou, P., additional, Zhou, R., additional, Zhou, X.X., additional, Zhu, C.G., additional, Zhu, F.R., additional, Zhu, H., additional, Zhu, K.J., additional, and Zuo, X., additional
Published: 2023
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41. Corrigendum to “Performance test of the electromagnetic particle detectors for the LHAASO experiment” [Nucl. Instrum. Methods Phys. Res. A 1001 (2021) 165193]

Author: Aharonian, F., An, Q., Axikegu, Bai, L.X., Bai, Y.X., Bao, Y.W., Bastieri, D., Bi, X.J., Bi, Y.J., Cai, H., Cai, J.T., Cao, Z., Chang, J., Chang, J.F., Chang, X.C., Chen, B.M., Chen, J., Chen, L., Chen, M.J., Chen, M.L., Chen, Q.H., Chen, S.H., Chen, S.Z., Chen, T.L., Chen, X.L., Chen, Y., Cheng, N., Cheng, Y.D., Cui, S.W., Cui, X.H., Cui, Y.D., Dai, B.Z., Dai, H.L., Dai, Z.G., Danzengluobu, della Volpe, D., Piazzoli, B. D’Ettorre, Dong, X.J., Fan, J.H., Fan, Y.Z., Fan, Z.X., Fang, J., Fang, K., Feng, C.F., Feng, L., Feng, S.H., Feng, Y.L., Gao, B., Gao, C.D., Gao, Q., Gao, W., Ge, M.M., Geng, L.S., Gong, G.H., Gou, Q.B., Gu, M.H., Guo, J.G., Guo, X.L., Guo, Y.Q., Guo, Y.Y., Han, Y.A., He, H.H., He, H.N., He, J.C., He, S.L., He, X.B., He, Y., Heller, M., Hor, Y.K., Hou, C., Hou, X., Hu, H.B., Hu, S., Hu, S.C., Hu, X.J., Huang, D.H., Huang, Q.L., Huang, W.H., Huang, X.T., Huang, Z.C., Ji, F., Ji, X.L., Jia, H.Y., Jia, K., Jiang, K., Jiang, Z.J., Jin, C., Kuleshov, D., Levochkin, K., Li, B., Li, B.B., Li, C., Li, F., Li, H., Li, H.B., Li, H.C., Li, H.Y., Li, J., Li, K., Li, W.L., Li, X., Li, X.R., Li, Y., Li, Y.Z., Li, Z., Liang, E.W., Liang, Y.F., Lin, S.J., Liu, B., Liu, C., Liu, D., Liu, H., Liu, H.D., Liu, J., Liu, J.L., Liu, J.S., Liu, J.Y., Liu, M.Y., Liu, R.Y., Liu, S.M., Liu, W., Liu, Y.N., Liu, Z.X., Long, W.J., Lu, R., Lv, H.K., Ma, B.Q., Ma, L.L., Ma, X.H., Mao, J.R., Masood, A., Mitthumsiri, W., Montaruli, T., Nan, Y.C., Pang, B.Y., Pattarakijwanich, P., Pei, Z.Y., Qi, M.Y., Ruffolo, D., Rulev, V., Sáiz, A., Shao, L., Shchegolev, O., Sheng, X.D., Shi, J.R., Song, H.C., Stenkin, Yu.V., Stepanov, V., Sun, Q.N., Sun, X.N., Sun, Z.B., Tam, P.H. T., Tang, Z.B., Tian, W.W., Wang, B.D., Wang, C., Wang, H., Wang, H.G., Wang, J.C., Wang, J.S., Wang, L.P., Wang, L.Y., Wang, R.N., Wang, W., Wang, X.G., Wang, X.J., Wang, X.Y., Wang, Y.D., Wang, Y.J., Wang, Y.P., Wang, Z., Wang, Z.H., Wang, Z.X., Wei, D.M., Wei, J.J., Wei, Y.J., Wen, T., Wu, C.Y., Wu, H.R., Wu, S., Wu, W.X., Wu, X.F., Xi, S.Q., Xia, J., Xia, J.J., Xiang, G.M., Xiao, G., Xiao, H.B., Xin, G.G., Xin, Y.L., Xing, Y., Xu, D.L., Xu, R.X., Xue, L., Yan, D.H., Yang, C.W., Yang, F.F., Yang, J.Y., Yang, L.L., Yang, M.J., Yang, R.Z., Yang, S.B., Yao, Y.H., Yao, Z.G., Ye, Y.M., Yin, L.Q., Yin, N., You, X.H., You, Z.Y., Yu, Y.H., Yuan, Q., Zeng, H.D., Zeng, T.X., Zeng, W., Zeng, Z.K., Zha, M., Zhai, X.X., Zhang, B.B., Zhang, H.M., Zhang, H.Y., Zhang, J.L., Zhang, J.W., Zhang, L., Zhang, L.X., Zhang, P.F., Zhang, P.P., Zhang, R., Zhang, S.R., Zhang, S.S., Zhang, X., Zhang, X.P., Zhang, Y., Zhang, Y.F., Zhang, Y.L., Zhao, B., Zhao, J., Zhao, L., Zhao, L.Z., Zhao, S.P., Zhao, X., Zheng, F., Zheng, Y., Zhou, B., Zhou, H., Zhou, J.N., Zhou, P., Zhou, R., Zhou, X.X., Zhu, C.G., Zhu, F.R., Zhu, H., Zhu, K.J., and Zuo, X.
Published: 2022
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42. Performance of LHAASO-WCDA and observation of the Crab Nebula as a standard candle *

Author: Aharonian, F., primary, An, Q., additional, Axikegu, 克古, additional, Bai, L.X., additional, Bai, Y.X., additional, Bao, Y.W., additional, Bastieri, D., additional, Bi, X.J., additional, Bi, Y.J., additional, Cai, H., additional, Cai, J.T., additional, Cao, Z., additional, Chang, J., additional, Chang, J.F., additional, Chang, X.C., additional, Chen, B.M., additional, Chen, J., additional, Chen, L., additional, Chen, M.J., additional, Chen, M.L., additional, Chen, Q.H., additional, Chen, S.H., additional, Chen, S.Z., additional, Chen, T.L., additional, Chen, X.L., additional, Chen, Y., additional, Cheng, N., additional, Cheng, Y.D., additional, Cui, S.W., additional, Cui, X.H., additional, Cui, Y.D., additional, Dai, B.Z., additional, Dai, H.L., additional, Dai, Z.G., additional, Danzengluobu, 罗布, additional, della Volpe, D., additional, Piazzoli, B. D'Ettorre, additional, Dong, X.J., additional, Fan, J.H., additional, Fan, Y.Z., additional, Fan, Z.X., additional, Fang, J., additional, Fang, K., additional, Feng, C.F., additional, Feng, L., additional, Feng, S.H., additional, Feng, Y.L., additional, Gao, B., additional, Gao, C.D., additional, Gao, Q., additional, Gao, W., additional, Ge, M.M., additional, Geng, L.S., additional, Gong, G.H., additional, Gou, Q.B., additional, Gu, M.H., additional, Guo, J.G., additional, Guo, X.L., additional, Guo, Y.Q., additional, Guo, Y.Y., additional, Han, Y.A., additional, He, H.H., additional, He, H.N., additional, He, J.C., additional, He, S.L., additional, He, X.B., additional, He, Y., additional, Heller, M., additional, Hor, Y.K., additional, Hou, C., additional, Hou, X., additional, Hu, H.B., additional, Hu, S., additional, Hu, S.C., additional, Hu, X.J., additional, Huang, D.H., additional, Huang, Q.L., additional, Huang, W.H., additional, Huang, X.T., additional, Huang, Z.C., additional, Ji, F., additional, Ji, X.L., additional, Jia, H.Y., additional, Jiang, K., additional, Jiang, Z.J., additional, Jin, C., additional, Kuleshov, D., additional, Levochkin, K., additional, Li, B.B., additional, Li, C., additional, Li, F., additional, Li, H.B., additional, Li, H.C., additional, Li, H.Y., additional, Li, J., additional, Li, K., additional, Li, W.L., additional, Li, X., additional, Li, X.R., additional, Li, Y., additional, Li, Y.Z., additional, Li, Z., additional, Liang, E.W., additional, Liang, Y.F., additional, Lin, S.J., additional, Liu, B., additional, Liu, C., additional, Liu, D., additional, Liu, H., additional, Liu, H.D., additional, Liu, J., additional, Liu, J.L., additional, Liu, J.S., additional, Liu, J.Y., additional, Liu, M.Y., additional, Liu, R.Y., additional, Liu, S.M., additional, Liu, W., additional, Liu, Y.N., additional, Liu, Z.X., additional, Long, W.J., additional, Lu, R., additional, Lv, H.K., additional, Ma, B.Q., additional, Ma, L.L., additional, Ma, X.H., additional, Mao, J.R., additional, Masood, A., additional, Mitthumsiri, W., additional, Montaruli, T., additional, Nan, Y.C., additional, Pang, B.Y., additional, Pattarakijwanich, P., additional, Pei, Z.Y., additional, Qi, M.Y., additional, Qiao, B.Q., additional, Ruffolo, D., additional, Rulev, V., additional, Sáiz, A., additional, Shao, L., additional, Shchegolev, O., additional, Sheng, X.D., additional, Shi, J.R., additional, Song, H.C., additional, Stenkin, Yu.V., additional, Stepanov, V., additional, Sun, Q.N., additional, Sun, X.N., additional, Sun, Z.B., additional, Tam, P.H.T., additional, Tang, Z.B., additional, Tian, W.W., additional, Wang, B.D., additional, Wang, C., additional, Wang, H., additional, Wang, H.G., additional, Wang, J.C., additional, Wang, J.S., additional, Wang, L.P., additional, Wang, L.Y., additional, Wang, R.N., additional, Wang, W., additional, Wang, X.G., additional, Wang, X.J., additional, Wang, X.Y., additional, Wang, Y.D., additional, Wang, Y.J., additional, Wang, Y.P., additional, Wang, Z., additional, Wang, Z.H., additional, Wang, Z.X., additional, Wei, D.M., additional, Wei, J.J., additional, Wei, Y.J., additional, Wen, T., additional, Wu, C.Y., additional, Wu, H.R., additional, Wu, S., additional, Wu, W.X., additional, Wu, X.F., additional, Xi, S.Q., additional, Xia, J., additional, Xia, J.J., additional, Xiang, G.M., additional, Xiao, G., additional, Xiao, H.B., additional, Xin, G.G., additional, Xin, Y.L., additional, Xing, Y., additional, Xu, D.L., additional, Xu, R.X., additional, Xue, L., additional, Yan, D.H., additional, Yang, C.W., additional, Yang, F.F., additional, Yang, J.Y., additional, Yang, L.L., additional, Yang, M.J., additional, Yang, R.Z., additional, Yang, S.B., additional, Yao, Y.H., additional, Yao, Z.G., additional, Ye, Y.M., additional, Yin, L.Q., additional, Yin, N., additional, You, X.H., additional, You, Z.Y., additional, Yu, Y.H., additional, Yuan, Q., additional, Zeng, H.D., additional, Zeng, T.X., additional, Zeng, W., additional, Zeng, Z.K., additional, Zha, M., additional, Zhai, X.X., additional, Zhang, B.B., additional, Zhang, H.M., additional, Zhang, H.Y., additional, Zhang, J.L., additional, Zhang, J.W., additional, Zhang, L., additional, Zhang, L.X., additional, Zhang, P.F., additional, Zhang, P.P., additional, Zhang, R., additional, Zhang, S.R., additional, Zhang, S.S., additional, Zhang, X., additional, Zhang, X.P., additional, Zhang, Y., additional, Zhang, Y.F., additional, Zhang, Y.L., additional, Zhao, B., additional, Zhao, J., additional, Zhao, L., additional, Zhao, L.Z., additional, Zhao, S.P., additional, Zheng, F., additional, Zheng, Y., additional, Zhou, B., additional, Zhou, H., additional, Zhou, J.N., additional, Zhou, P., additional, Zhou, R., additional, Zhou, X.X., additional, Zhu, C.G., additional, Zhu, F.R., additional, Zhu, H., additional, Zhu, K.J., additional, Zuo, X., additional, and Collaboration), (The LHAASO, additional
Published: 2021
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43. Observation of the Crab Nebula with LHAASO-KM2A − a performance study *

Author: Aharonian, F., primary, An, Q., additional, Axikegu, 克古, additional, Bai, L. X., additional, Bai, Y. X., additional, Bao, Y. W., additional, Bastieri, D., additional, Bi, X. J., additional, Bi, Y. J., additional, Cai, H., additional, Cai, J. T., additional, Cao, Z., additional, Chang, J., additional, Chang, J. F., additional, Chang, X. C., additional, Chen, B. M., additional, Chen, J., additional, Chen, L., additional, Chen, M. J., additional, Chen, M. L., additional, Chen, Q. H., additional, Chen, S. H., additional, Chen, S. Z., additional, Chen, T. L., additional, Chen, X. L., additional, Chen, Y., additional, Cheng, N., additional, Cheng, Y. D., additional, Cui, S. W., additional, Cui, X. H., additional, Cui, Y. D., additional, Dai, B. Z., additional, Dai, H. L., additional, Dai, Z. G., additional, Danzengluobu, 罗布, additional, Volpe, D. della, additional, Piazzoli, B. D'Ettorre, additional, Dong, X. J., additional, Fan, J. H., additional, Fan, Y. Z., additional, Fan, Z. X., additional, Fang, J., additional, Fang, K., additional, Feng, C. F., additional, Feng, L., additional, Feng, S. H., additional, Feng, Y. L., additional, Gao, B., additional, Gao, C. D., additional, Gao, Q., additional, Gao, W., additional, Ge, M. M., additional, Geng, L. S., additional, Gong, G. H., additional, Gou, Q. B., additional, Gu, M. H., additional, Guo, J. G., additional, Guo, X. L., additional, Guo, Y. Q., additional, Guo, Y. Y., additional, Han, Y. A., additional, He, H. H., additional, He, H. N., additional, He, J. C., additional, He, S. L., additional, He, X. B., additional, He, Y., additional, Heller, M., additional, Hor, Y. K., additional, Hou, C., additional, Hou, X., additional, Hu, H. B., additional, Hu, S., additional, Hu, S. C., additional, Hu, X. J., additional, Huang, D. H., additional, Huang, Q. L., additional, Huang, W. H., additional, Huang, X. T., additional, Huang, Z. C., additional, Ji, F., additional, Ji, X. L., additional, Jia, H. Y., additional, Jiang, K., additional, Jiang, Z. J., additional, Jin, C., additional, Kuleshov, D., additional, Levochkin, K., additional, Li, B. B., additional, Li, C., additional, Li, F., additional, Li, H. B., additional, Li, H. C., additional, Li, H. Y., additional, Li, J., additional, Li, K., additional, Li, W. L., additional, Li, X., additional, Li, X. R., additional, Li, Y., additional, Li, Y. Z., additional, Li, Z., additional, Liang, E. W., additional, Liang, Y. F., additional, Lin, S. J., additional, Liu, B., additional, Liu, C., additional, Liu, D., additional, Liu, H., additional, Liu, H. D., additional, Liu, J., additional, Liu, J. L., additional, Liu, J. S., additional, Liu, J. Y., additional, Liu, M. Y., additional, Liu, R. Y., additional, Liu, S. M., additional, Liu, W., additional, Liu, Y. N., additional, Liu, Z. X., additional, Long, W. J., additional, Lu, R., additional, Lv, H. K., additional, Ma, B. Q., additional, Ma, L. L., additional, Ma, X. H., additional, Mao, J. R., additional, Masood, A., additional, Mitthumsiri, W., additional, Montaruli, T., additional, Nan, Y. C., additional, Pang, B. Y., additional, Pattarakijwanich, P., additional, Pei, Z. Y., additional, Qi, M. Y., additional, Ruffolo, D., additional, Rulev, V., additional, Sáiz, A., additional, Shao, L., additional, Shchegolev, O., additional, Sheng, X. D., additional, Shi, J. R., additional, Song, H. C., additional, Stenkin, Yu. V., additional, Stepanov, V., additional, Sun, Q. N., additional, Sun, X. N., additional, Sun, Z. B., additional, Tam, P. H. T., additional, Tang, Z. B., additional, Tian, W. W., additional, Wang, B. D., additional, Wang, C., additional, Wang, H., additional, Wang, H. G., additional, Wang, J. C., additional, Wang, J. S., additional, Wang, L. P., additional, Wang, L. Y., additional, Wang, R. N., additional, Wang, W., additional, Wang, X. G., additional, Wang, X. J., additional, Wang, X. Y., additional, Wang, Y. D., additional, Wang, Y. J., additional, Wang, Y. P., additional, Wang, Z., additional, Wang, Z. H., additional, Wang, Z. X., additional, Wei, D. M., additional, Wei, J. J., additional, Wei, Y. J., additional, Wen, T., additional, Wu, C. Y., additional, Wu, H. R., additional, Wu, S., additional, Wu, W. X., additional, Wu, X. F., additional, Xi, S. Q., additional, Xia, J., additional, Xia, J. J., additional, Xiang, G. M., additional, Xiao, G., additional, Xiao, H. B., additional, Xin, G. G., additional, Xin, Y. L., additional, Xing, Y., additional, Xu, D. L., additional, Xu, R. X., additional, Xue, L., additional, Yan, D. H., additional, Yang, C. W., additional, Yang, F. F., additional, Yang, J. Y., additional, Yang, L. L., additional, Yang, M. J., additional, Yang, R. Z., additional, Yang, S. B., additional, Yao, Y. H., additional, Yao, Z. G., additional, Ye, Y. M., additional, Yin, L. Q., additional, Yin, N., additional, You, X. H., additional, You, Z. Y., additional, Yu, Y. H., additional, Yuan, Q., additional, Zeng, H. D., additional, Zeng, T. X., additional, Zeng, W., additional, Zeng, Z. K., additional, Zha, M., additional, Zhai, X. X., additional, Zhang, B. B., additional, Zhang, H. M., additional, Zhang, H. Y., additional, Zhang, J. L., additional, Zhang, J. W., additional, Zhang, L., additional, Zhang, L. X., additional, Zhang, P. F., additional, Zhang, P. P., additional, Zhang, R., additional, Zhang, S. R., additional, Zhang, S. S., additional, Zhang, X., additional, Zhang, X. P., additional, Zhang, Y., additional, Zhang, Y. F., additional, Zhang, Y. L., additional, Zhao, B., additional, Zhao, J., additional, Zhao, L., additional, Zhao, L. Z., additional, Zhao, S. P., additional, Zheng, F., additional, Zheng, Y., additional, Zhou, B., additional, Zhou, H., additional, Zhou, J. N., additional, Zhou, P., additional, Zhou, R., additional, Zhou, X. X., additional, Zhu, C. G., additional, Zhu, F. R., additional, Zhu, H., additional, Zhu, K. J., additional, and Zuo, X., additional
Published: 2021
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44. Physical properties of RR Lyrae variables in Galactic globular clusters and dwarf spheroidal galaxies

Author: Benkortem, S, primary, Tanakul, N, additional, Suwannajak, C, additional, Pattarakijwanich, P, additional, and Yuma, S, additional
Published: 2019
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45. Ongoing Variability in Transits of the Disintegrating Rocky Exoplanet K2-22b

Author: Colon, K., Zhou, G., Shporer, A., Collins, K., Bieryla, A., Latham, D., Espinoza, N., Murgas, F., Pattarakijwanich, P., and Awiphan, S.
Subjects: Astrophysics::Earth and Planetary Astrophysics
Abstract: The discovery of the first disintegrating exoplanet opened a new door in the field of exoplanets. The rocky exoplanet K2-22b is just the third known disintegrating exoplanet, and it orbits an M dwarf with a period of just 9 hr. It was discovered by NASA's K2 mission in 2014. Sanchis- Ojeda et al. (2015) presented the analysis of the K2 observations that were obtained between May and August 2014 and 15 ground-based follow-up light curves obtained between January and March 2015. From these data, Sanchis-Ojeda et al. (2015) measured rapidly variable transit depths for K2-22b ranging from 0% to 1.3%. A wavelength-dependent transit light curve shape was also measured during one particularly deep transit, supporting dust scattering during the transit. In addition, K2-22b appears to have both a leading and trailing dust tail. The star itself also exhibits photometric variability at the 1% level with a rotation period of 15 days. We will present results from 45 ground-based photometric observations of the K2-22 system collected between December 2016 and May 2017, which we use to investigate the evolution of the transit of the disintegrating planet K2-22b since 2015. In these new observations we recover the transit at multiple epochs and measure a typical depth of
Published: 2018

46. Stringent Tests of Lorentz Invariance Violation from LHAASO Observations of GRB 221009A.

Author: Cao Z, Aharonian F, Axikegu, Bai YX, Bao YW, Bastieri D, Bi XJ, Bi YJ, Bian W, Bukevich AV, Cao Q, Cao WY, Cao Z, Chang J, Chang JF, Chen AM, Chen ES, Chen HX, Chen L, Chen L, Chen L, Chen MJ, Chen ML, Chen QH, Chen S, Chen SH, Chen SZ, Chen TL, Chen Y, Cheng N, Cheng YD, Cui MY, Cui SW, Cui XH, Cui YD, Dai BZ, Dai HL, Dai ZG, Danzengluobu, Dong XQ, Duan KK, Fan JH, Fan YZ, Fang J, Fang JH, Fang K, Feng CF, Feng H, Feng L, Feng SH, Feng XT, Feng Y, Feng YL, Gabici S, Gao B, Gao CD, Gao Q, Gao W, Gao WK, Ge MM, Geng LS, Giacinti G, Gong GH, Gou QB, Gu MH, Guo FL, Guo XL, Guo YQ, Guo YY, Han YA, Hasan M, He HH, He HN, He JY, He Y, Hor YK, Hou BW, Hou C, Hou X, Hu HB, Hu Q, Hu SC, Huang DH, Huang TQ, Huang WJ, Huang XT, Huang XY, Huang Y, Ji XL, Jia HY, Jia K, Jiang K, Jiang XW, Jiang ZJ, Jin M, Kang MM, Karpikov I, Kuleshov D, Kurinov K, Li BB, Li CM, Li C, Li C, Li D, Li F, Li HB, Li HC, Li J, Li J, Li K, Li SD, Li WL, Li WL, Li XR, Li X, Li YZ, Li Z, Li Z, Liang EW, Liang YF, Lin SJ, Liu B, Liu C, Liu D, Liu DB, Liu H, Liu HD, Liu J, Liu JL, Liu MY, Liu RY, Liu SM, Liu W, Liu Y, Liu YN, Luo Q, Luo Y, Lv HK, Ma BQ, Ma LL, Ma XH, Mao JR, Min Z, Mitthumsiri W, Mu HJ, Nan YC, Neronov A, Ou LJ, Pattarakijwanich P, Pei ZY, Qi JC, Qi MY, Qiao BQ, Qin JJ, Raza A, Ruffolo D, Sáiz A, Saeed M, Semikoz D, Shao L, Shchegolev O, Sheng XD, Shu FW, Song HC, Stenkin YV, Stepanov V, Su Y, Sun DX, Sun QN, Sun XN, Sun ZB, Takata J, Tam PHT, Tang QW, Tang R, Tang ZB, Tian WW, Wang C, Wang CB, Wang GW, Wang HG, Wang HH, Wang JC, Wang K, Wang K, Wang LP, Wang LY, Wang PH, Wang R, Wang W, Wang XG, Wang XY, Wang Y, Wang YD, Wang YJ, Wang ZH, Wang ZX, Wang Z, Wang Z, Wei DM, Wei JJ, Wei YJ, Wen T, Wu CY, Wu HR, Wu QW, Wu S, Wu XF, Wu YS, Xi SQ, Xia J, Xiang GM, Xiao DX, Xiao G, Xin YL, Xing Y, Xiong DR, Xiong Z, Xu DL, Xu RF, Xu RX, Xu WL, Xue L, Yan DH, Yan JZ, Yan T, Yang CW, Yang CY, Yang F, Yang FF, Yang LL, Yang MJ, Yang RZ, Yang WX, Yao YH, Yao ZG, Yin LQ, Yin N, You XH, You ZY, Yu YH, Yuan Q, Yue H, Zeng HD, Zeng TX, Zeng W, Zha M, Zhang BB, Zhang F, Zhang H, Zhang HM, Zhang HY, Zhang JL, Zhang L, Zhang PF, Zhang PP, Zhang R, Zhang SB, Zhang SR, Zhang SS, Zhang X, Zhang XP, Zhang YF, Zhang Y, Zhang Y, Zhao B, Zhao J, Zhao L, Zhao LZ, Zhao SP, Zhao XH, Zheng F, Zhong WJ, Zhou B, Zhou H, Zhou JN, Zhou M, Zhou P, Zhou R, Zhou XX, Zhou XX, Zhu BY, Zhu CG, Zhu FR, Zhu H, Zhu KJ, Zou YC, and Zuo X
Abstract: On 9 October 2022, the Large High Altitude Air Shower Observatory (LHAASO) reported the observation of the very early TeV afterglow of the brightest-of-all-time gamma-ray burst 221009A, recording the highest photon statistics in the TeV band ever obtained from a gamma-ray burst. We use this unique observation to place stringent constraints on the energy dependence of the speed of light in vacuum, a manifestation of Lorentz invariance violation (LIV) predicted by some quantum gravity (QG) theories. Our results show that the 95% confidence level lower limits on the QG energy scales are E_{QG,1}>10 times the Planck energy E_{Pl} for the linear LIV effect, and E_{QG,2}>6×10^{-8}E_{Pl} for the quadratic LIV effect. Our limits on the quadratic LIV case improve previous best bounds by factors of 5-7.
Published: 2024
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47. Constraints on Ultraheavy Dark Matter Properties from Dwarf Spheroidal Galaxies with LHAASO Observations.

Author: Cao Z, Aharonian F, An Q, Axikegu, Bai YX, Bao YW, Bastieri D, Bi XJ, Bi YJ, Cai JT, Cao Q, Cao WY, Cao Z, Chang J, Chang JF, Chen AM, Chen ES, Chen L, Chen L, Chen L, Chen MJ, Chen ML, Chen QH, Chen SH, Chen SZ, Chen TL, Chen Y, Cheng N, Cheng YD, Cui MY, Cui SW, Cui XH, Cui YD, Dai BZ, Dai HL, Dai ZG, Danzengluobu, Della Volpe D, Dong XQ, Duan KK, Fan JH, Fan YZ, Fang J, Fang K, Feng CF, Feng L, Feng SH, Feng XT, Feng YL, Gabici S, Gao B, Gao CD, Gao LQ, Gao Q, Gao W, Gao WK, Ge MM, Geng LS, Giacinti G, Gong GH, Gou QB, Gu MH, Guo FL, Guo XL, Guo YQ, Guo YY, Han YA, He HH, He HN, He JY, He XB, He Y, Heller M, Hor YK, Hou BW, Hou C, Hou X, Hu HB, Hu Q, Hu SC, Huang DH, Huang TQ, Huang WJ, Huang XT, Huang XY, Huang Y, Huang ZC, Ji XL, Jia HY, Jia K, Jiang K, Jiang XW, Jiang ZJ, Jin M, Kang MM, Ke T, Kuleshov D, Kurinov K, Li BB, Li C, Li C, Li D, Li F, Li HB, Li HC, Li HY, Li J, Li J, Li J, Li K, Li WL, Li WL, Li XR, Li X, Li YZ, Li Z, Li Z, Liang EW, Liang YF, Lin SJ, Liu B, Liu C, Liu D, Liu H, Liu HD, Liu J, Liu JL, Liu JY, Liu MY, Liu RY, Liu SM, Liu W, Liu Y, Liu YN, Lu R, Luo Q, Lv HK, Ma BQ, Ma LL, Ma XH, Mao JR, Min Z, Mitthumsiri W, Mu HJ, Nan YC, Neronov A, Ou ZW, Pang BY, Pattarakijwanich P, Pei ZY, Qi MY, Qi YQ, Qiao BQ, Qin JJ, Ruffolo D, Sáiz A, Semikoz D, Shao CY, Shao L, Shchegolev O, Sheng XD, Shu FW, Song HC, Stenkin YV, Stepanov V, Su Y, Sun QN, Sun XN, Sun ZB, Tam PHT, Tang QW, Tang ZB, Tian WW, Wang C, Wang CB, Wang GW, Wang HG, Wang HH, Wang JC, Wang K, Wang LP, Wang LY, Wang PH, Wang R, Wang W, Wang XG, Wang XY, Wang Y, Wang YD, Wang YJ, Wang ZH, Wang ZX, Wang Z, Wang Z, Wei DM, Wei JJ, Wei YJ, Wen T, Wu CY, Wu HR, Wu S, Wu XF, Wu YS, Xi SQ, Xia J, Xia JJ, Xiang GM, Xiao DX, Xiao G, Xin GG, Xin YL, Xing Y, Xiong Z, Xu DL, Xu RF, Xu RX, Xu WL, Xue L, Yan DH, Yan JZ, Yan T, Yang CW, Yang F, Yang FF, Yang HW, Yang JY, Yang LL, Yang MJ, Yang RZ, Yang SB, Yao YH, Yao ZG, Ye YM, Yin LQ, Yin N, You XH, You ZY, Yu YH, Yuan Q, Yue H, Zeng HD, Zeng TX, Zeng W, Zha M, Zhang BB, Zhang F, Zhang HM, Zhang HY, Zhang JL, Zhang LX, Zhang L, Zhang PF, Zhang PP, Zhang R, Zhang SB, Zhang SR, Zhang SS, Zhang X, Zhang XP, Zhang YF, Zhang Y, Zhang Y, Zhao B, Zhao J, Zhao L, Zhao LZ, Zhao SP, Zheng F, Zhou B, Zhou H, Zhou JN, Zhou M, Zhou P, Zhou R, Zhou XX, Zhu CG, Zhu FR, Zhu H, Zhu KJ, and Zuo X
Abstract: In this Letter we try to search for signals generated by ultraheavy dark matter at the Large High Altitude Air Shower Observatory (LHAASO) data. We look for possible γ rays by dark matter annihilation or decay from 16 dwarf spheroidal galaxies in the field of view of the LHAASO. Dwarf spheroidal galaxies are among the most promising targets for indirect detection of dark matter that have low fluxes of astrophysical γ-ray background while having large amount of dark matter. By analyzing more than 700 days of observational data at LHAASO, no significant dark matter signal from 1 TeV to 1 EeV is detected. Accordingly we derive the most stringent constraints on the ultraheavy dark matter annihilation cross section up to EeV. The constraints on the lifetime of dark matter in decay mode are also derived.
Published: 2024
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48. Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A.

Author: Cao Z, Aharonian F, Axikegu, Bai YX, Bao YW, Bastieri D, Bi XJ, Bi YJ, Bian W, Bukevich AV, Cao Q, Cao WY, Cao Z, Chang J, Chang JF, Chen AM, Chen ES, Chen HX, Chen L, Chen L, Chen L, Chen MJ, Chen ML, Chen QH, Chen S, Chen SH, Chen SZ, Chen TL, Chen Y, Cheng N, Cheng YD, Cui MY, Cui SW, Cui XH, Cui YD, Dai BZ, Dai HL, Dai ZG, Danzengluobu, Dong XQ, Duan KK, Fan JH, Fan YZ, Fang J, Fang JH, Fang K, Feng CF, Feng H, Feng L, Feng SH, Feng XT, Feng Y, Feng YL, Gabici S, Gao B, Gao CD, Gao Q, Gao W, Gao WK, Ge MM, Geng LS, Giacinti G, Gong GH, Gou QB, Gu MH, Guo FL, Guo XL, Guo YQ, Guo YY, Han YA, Hasan M, He HH, He HN, He JY, He Y, Hor YK, Hou BW, Hou C, Hou X, Hu HB, Hu Q, Hu SC, Huang DH, Huang TQ, Huang WJ, Huang XT, Huang XY, Huang Y, Ji XL, Jia HY, Jia K, Jiang K, Jiang XW, Jiang ZJ, Jin M, Kang MM, Karpikov I, Kuleshov D, Kurinov K, Li BB, Li CM, Li C, Li C, Li D, Li F, Li HB, Li HC, Li J, Li J, Li K, Li SD, Li WL, Li WL, Li XR, Li X, Li YZ, Li Z, Li Z, Liang EW, Liang YF, Lin SJ, Liu B, Liu C, Liu D, Liu DB, Liu H, Liu HD, Liu J, Liu JL, Liu MY, Liu RY, Liu SM, Liu W, Liu Y, Liu YN, Luo Q, Luo Y, Lv HK, Ma BQ, Ma LL, Ma XH, Mao JR, Min Z, Mitthumsiri W, Mu HJ, Nan YC, Neronov A, Ou LJ, Pattarakijwanich P, Pei ZY, Qi JC, Qi MY, Qiao BQ, Qin JJ, Raza A, Ruffolo D, Sáiz A, Saeed M, Semikoz D, Shao L, Shchegolev O, Sheng XD, Shu FW, Song HC, Stenkin YV, Stepanov V, Su Y, Sun DX, Sun QN, Sun XN, Sun ZB, Takata J, Tam PHT, Tang QW, Tang R, Tang ZB, Tian WW, Wang C, Wang CB, Wang GW, Wang HG, Wang HH, Wang JC, Wang K, Wang K, Wang LP, Wang LY, Wang PH, Wang R, Wang W, Wang XG, Wang XY, Wang Y, Wang YD, Wang YJ, Wang ZH, Wang ZX, Wang Z, Wang Z, Wei DM, Wei JJ, Wei YJ, Wen T, Wu CY, Wu HR, Wu QW, Wu S, Wu XF, Wu YS, Xi SQ, Xia J, Xiang GM, Xiao DX, Xiao G, Xin YL, Xing Y, Xiong DR, Xiong Z, Xu DL, Xu RF, Xu RX, Xu WL, Xue L, Yan DH, Yan JZ, Yan T, Yang CW, Yang CY, Yang F, Yang FF, Yang LL, Yang MJ, Yang RZ, Yang WX, Yao YH, Yao ZG, Yin LQ, Yin N, You XH, You ZY, Yu YH, Yuan Q, Yue H, Zeng HD, Zeng TX, Zeng W, Zha M, Zhang BB, Zhang F, Zhang H, Zhang HM, Zhang HY, Zhang JL, Zhang L, Zhang PF, Zhang PP, Zhang R, Zhang SB, Zhang SR, Zhang SS, Zhang X, Zhang XP, Zhang YF, Zhang Y, Zhang Y, Zhao B, Zhao J, Zhao L, Zhao LZ, Zhao SP, Zhao XH, Zheng F, Zhong WJ, Zhou B, Zhou H, Zhou JN, Zhou M, Zhou P, Zhou R, Zhou XX, Zhou XX, Zhu BY, Zhu CG, Zhu FR, Zhu H, Zhu KJ, Zou YC, and Zuo X
Abstract: We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15 PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.
Published: 2024
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49. A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst.

Author: Cao Z, Aharonian F, An Q, Axikegu, Bai LX, Bai YX, Bao YW, Bastieri D, Bi XJ, Bi YJ, Cai JT, Cao Q, Cao WY, Cao Z, Chang J, Chang JF, Chen ES, Chen L, Chen L, Chen L, Chen MJ, Chen ML, Chen QH, Chen SH, Chen SZ, Chen TL, Chen Y, Cheng HL, Cheng N, Cheng YD, Cui SW, Cui XH, Cui YD, Dai BZ, Dai HL, Dai ZG, Danzengluobu, Della Volpe D, Dong XQ, Duan KK, Fan JH, Fan YZ, Fang J, Fang K, Feng CF, Feng L, Feng SH, Feng XT, Feng YL, Gao B, Gao CD, Gao LQ, Gao Q, Gao W, Gao WK, Ge MM, Geng LS, Gong GH, Gou QB, Gu MH, Guo FL, Guo XL, Guo YQ, Guo YY, Han YA, He HH, He HN, He JY, He XB, He Y, Heller M, Hor YK, Hou BW, Hou C, Hou X, Hu HB, Hu Q, Hu SC, Huang DH, Huang TQ, Huang WJ, Huang XT, Huang XY, Huang Y, Huang ZC, Ji XL, Jia HY, Jia K, Jiang K, Jiang XW, Jiang ZJ, Jin M, Kang MM, Ke T, Kuleshov D, Kurinov K, Li BB, Li C, Li C, Li D, Li F, Li HB, Li HC, Li HY, Li J, Li J, Li J, Li K, Li WL, Li WL, Li XR, Li X, Li YZ, Li Z, Li Z, Liang EW, Liang YF, Lin SJ, Liu B, Liu C, Liu D, Liu H, Liu HD, Liu J, Liu JL, Liu JL, Liu JS, Liu JY, Liu MY, Liu RY, Liu SM, Liu W, Liu Y, Liu YN, Long WJ, Lu R, Luo Q, Lv HK, Ma BQ, Ma LL, Ma XH, Mao JR, Min Z, Mitthumsiri W, Nan YC, Ou ZW, Pang BY, Pattarakijwanich P, Pei ZY, Qi MY, Qi YQ, Qiao BQ, Qin JJ, Ruffolo D, Sáiz A, Shao CY, Shao L, Shchegolev O, Sheng XD, Song HC, Stenkin YV, Stepanov V, Su Y, Sun QN, Sun XN, Sun ZB, Tam PHT, Tang ZB, Tian WW, Wang C, Wang CB, Wang GW, Wang HG, Wang HH, Wang JC, Wang JS, Wang K, Wang LP, Wang LY, Wang PH, Wang R, Wang W, Wang XG, Wang XY, Wang Y, Wang YD, Wang YJ, Wang ZH, Wang ZX, Wang Z, Wang Z, Wei DM, Wei JJ, Wei YJ, Wen T, Wu CY, Wu HR, Wu S, Wu XF, Wu YS, Xi SQ, Xia J, Xia JJ, Xiang GM, Xiao DX, Xiao G, Xin GG, Xin YL, Xing Y, Xiong Z, Xu DL, Xu RF, Xu RX, Xue L, Yan DH, Yan JZ, Yan T, Yang CW, Yang F, Yang FF, Yang HW, Yang JY, Yang LL, Yang MJ, Yang RZ, Yang SB, Yao YH, Yao ZG, Ye YM, Yin LQ, Yin N, You XH, You ZY, Yu YH, Yuan Q, Yue H, Zeng HD, Zeng TX, Zeng W, Zeng ZK, Zha M, Zhang B, Zhang BB, Zhang F, Zhang HM, Zhang HY, Zhang JL, Zhang LX, Zhang L, Zhang PF, Zhang PP, Zhang R, Zhang SB, Zhang SR, Zhang SS, Zhang X, Zhang XP, Zhang YF, Zhang Y, Zhang Y, Zhao B, Zhao J, Zhao L, Zhao LZ, Zhao SP, Zheng F, Zheng JH, Zhou B, Zhou H, Zhou JN, Zhou P, Zhou R, Zhou XX, Zhu CG, Zhu FR, Zhu H, Zhu KJ, and Zuo X
Abstract: Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory (LHAASO) of the bright GRB 221009A, which serendipitously occurred within the instrument's field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger and then rose to a peak ~10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle of ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.
Published: 2023
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50. Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations.

Author: Cao Z, Aharonian F, An Q, Axikegu, Bai LX, Bai YX, Bao YW, Bastieri D, Bi XJ, Bi YJ, Cai JT, Cao Z, Chang J, Chang JF, Chen ES, Chen L, Chen L, Chen L, Chen MJ, Chen ML, Chen QH, Chen SH, Chen SZ, Chen TL, Chen Y, Cheng HL, Cheng N, Cheng YD, Cui SW, Cui XH, Cui YD, D'Ettorre Piazzoli B, Dai BZ, Dai HL, Dai ZG, Danzengluobu, Della Volpe D, Duan KK, Fan JH, Fan YZ, Fan ZX, Fang J, Fang K, Feng CF, Feng L, Feng SH, Feng XT, Feng YL, Gao B, Gao CD, Gao LQ, Gao Q, Gao W, Gao WK, Ge MM, Geng LS, Gong GH, Gou QB, Gu MH, Guo FL, Guo JG, Guo XL, Guo YQ, Guo YY, Han YA, He HH, He HN, He SL, He XB, He Y, Heller M, Hor YK, Hou C, Hou X, Hu HB, Hu Q, Hu S, Hu SC, Hu XJ, Huang DH, Huang WH, Huang XT, Huang XY, Huang Y, Huang ZC, Ji XL, Jia HY, Jia K, Jiang K, Jiang ZJ, Jin M, Kang MM, Ke T, Kuleshov D, Levochkin K, Li BB, Li C, Li C, Li F, Li HB, Li HC, Li HY, Li J, Li J, Li J, Li K, Li WL, Li XR, Li X, Li X, Li YZ, Li Z, Li Z, Liang EW, Liang YF, Lin SJ, Liu B, Liu C, Liu D, Liu H, Liu HD, Liu J, Liu JL, Liu JS, Liu JY, Liu MY, Liu RY, Liu SM, Liu W, Liu Y, Liu YN, Long WJ, Lu R, Luo Q, Lv HK, Ma BQ, Ma LL, Ma XH, Mao JR, Masood A, Min Z, Mitthumsiri W, Nan YC, Ou ZW, Pang BY, Pattarakijwanich P, Pei ZY, Qi MY, Qi YQ, Qiao BQ, Qin JJ, Ruffolo D, Sáiz A, Shao CY, Shao L, Shchegolev O, Sheng XD, Shi JY, Song HC, Stenkin YV, Stepanov V, Su Y, Sun QN, Sun XN, Sun ZB, Tam PHT, Tang ZB, Tian WW, Wang BD, Wang C, Wang H, Wang HG, Wang JC, Wang JS, Wang LP, Wang LY, Wang R, Wang RN, Wang W, Wang XG, Wang XY, Wang Y, Wang YD, Wang YJ, Wang YP, Wang ZH, Wang ZX, Wang Z, Wang Z, Wei DM, Wei JJ, Wei YJ, Wen T, Wu CY, Wu HR, Wu S, Wu XF, Wu YS, Xi SQ, Xia J, Xia JJ, Xiang GM, Xiao DX, Xiao G, Xin GG, Xin YL, Xing Y, Xiong Z, Xu DL, Xu RX, Xue L, Yan DH, Yan JZ, Yang CW, Yang FF, Yang HW, Yang JY, Yang LL, Yang MJ, Yang RZ, Yang SB, Yao YH, Yao ZG, Ye YM, Yin LQ, Yin N, You XH, You ZY, Yu YH, Yuan Q, Yue H, Zeng HD, Zeng TX, Zeng W, Zeng ZK, Zha M, Zhai XX, Zhang BB, Zhang F, Zhang HM, Zhang HY, Zhang JL, Zhang LX, Zhang L, Zhang L, Zhang PF, Zhang PP, Zhang R, Zhang SB, Zhang SR, Zhang SS, Zhang X, Zhang XP, Zhang YF, Zhang YL, Zhang Y, Zhang Y, Zhao B, Zhao J, Zhao L, Zhao LZ, Zhao SP, Zheng F, Zheng Y, Zhou B, Zhou H, Zhou JN, Zhou P, Zhou R, Zhou XX, Zhu CG, Zhu FR, Zhu H, Zhu KJ, Zuo X, Ando S, Chianese M, Fiorillo DFG, Miele G, and Ng KCY
Abstract: The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9} GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.
Published: 2022
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