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1. Construction and on-site performance of the LHAASO WFCTA camera

Author

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

Subjects
Photomultiplier, Physics - Instrumentation and Detectors, Physics and Astronomy (miscellaneous), FOS: Physical sciences, QC770-798, Astrophysics, 01 natural sciences, High Energy Physics - Experiment, law.invention, Telescope, High Energy Physics - Experiment (hep-ex), Silicon photomultiplier, Optics, Observatory, law, Nuclear and particle physics. Atomic energy. Radioactivity, 0103 physical sciences, 010306 general physics, Engineering (miscellaneous), Instrumentation and Methods for Astrophysics (astro-ph.IM), Cherenkov radiation, Physics, 010308 nuclear & particles physics, business.industry, Instrumentation and Detectors (physics.ins-det), Avalanche photodiode, Cherenkov Telescope Array, QB460-466, Air shower, Astrophysics - Instrumentation and Methods for Astrophysics, business
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
2021

2. Measurement of the Cosmic Ray Helium Energy Spectrum from 70 GeV to 80 TeV with the DAMPE Space Mission

Author

Fengtao Zhang, Y. F. Wang, Y. Y. Huang, Xiangpeng Guo, Jinfei Wu, D. Droz, J. N. Rao, Jinglai Duan, Yang Haibo, C. Liu, D. M. Wei, Zongye Zhang, X. Y. Ma, P. Azzarello, P. Fusco, Z. Y. Sun, Niu Xiaoyang, I. De Mitri, W. Zhang, Cihang Luo, C. Q. Feng, Yu Xing Cui, X. X. Li, M. S. Cai, Z.-Q. Shen, G. Marsella, X. L. Wang, S. Wang, F. Loparco, Guan Wen Yuan, Y. F. Wei, Jin Chang, Y. J. Zhang, Giacinto Donvito, W. X. Peng, J. L. Chen, Q. An, S. B. Liu, S. C. Wen, F. Gargano, Xiulian Pan, Y. Z. Gong, Cang Zhao, Yuqing Fan, T. S. Cui, H. T. Xu, A. De Benedittis, E. Catanzani, M. M. Salinas, Y. H. Yu, Zhao-Min Wang, Yun Long Zhang, Andrii Tykhonov, Wei Liu, Dingsong Wu, Zhenyu Zhang, Yifan Yang, G. F. Xue, Fang Fang, Pengtao Yang, M. Di Santo, R. Qiao, Yaohui Zhang, Xian Qiang Li, X. J. Bi, Chuan Yue, Min Gao, Z. Q. Xia, Shumei Wu, X. Y. Peng, M. M. Ma, Wenhan Jiang, J. Z. Wang, F. C. T. Barbato, M. Stolpovskiy, Hengchang Liu, F. Alemanno, P. Bernardini, J. J. Wei, Lihui Wu, Yujuan Liu, J. Liu, Yao Ming Liang, Z. Xu, A. Parenti, L. Feng, Yun-Zhi Zhang, A. Ruina, D. Mo, M. Y. Cui, Xin Wu, L. Silveri, Jun-jun Guo, Yu-Sa Wang, Hong Yun Zhao, W. Li, Hu-Rong Yao, Jinyuo Song, Z. Z. Xu, Z. X. Dong, Yan Fang Wang, Kun Fang, Y. Zhang, A. D'Amone, H. Su, Meng Su, A. Kotenko, Maria Ionica, Jie Kong, Shi-Jun Lei, Sheng Xia Zhang, Q. Yuan, Guangshun Huang, R. R. Fan, Peng-Xiong Ma, Xun Feng Zhao, Zhi Hui Xu, S.X. Li, A. Surdo, Yu-Xuan Zhu, X. J. Teng, Tie-Kuang Dong, W. H. Shen, Z. T. Shen, D. D'Urso, Zu-Cheng Chen, L. G. Wang, Dong Ya Guo, Xiaoyuan Huang, Y. M. Hu, F. de Palma, Hao Ting Dai, C. Perrina, Tianxiao Ma, Donghong Chen, Kai-Kai Duan, Maksym Deliyergiyev, D. Kyratzis, K. Gong, Chengrui Zhou, Mn Mazziotta, G. Z. Shang, Shuang Xue Han, J. J. Zang, Huaguang Wang, Alemanno F., An Q., Azzarello P., Barbato F.C.T., Bernardini P., Bi X.J., Cai M.S., Catanzani E., Chang J., Chen D.Y., Chen J.L., Chen Z.F., Cui M.Y., Cui T.S., Cui Y.X., Dai H.T., D'amone A., De Benedittis A., De Mitri I., De Palma F., Deliyergiyev M., Di Santo M., Dong T.K., Dong Z.X., Donvito G., Droz D., Duan J.L., Duan K.K., D'urso D., Fan R.R., Fan Y.Z., Fang K., Fang F., Feng C.Q., Feng L., Fusco P., Gao M., Gargano F., Gong K., Gong Y.Z., Guo D.Y., Guo J.H., Guo X.L., Han S.X., Hu Y.M., Huang G.S., Huang X.Y., Huang Y.Y., Ionica M., Jiang W., Kong J., Kotenko A., Kyratzis D., Lei S.J., Li S., Li W.L., Li X., Li X.Q., Liang Y.M., Liu C.M., Liu H., Liu J., Liu S.B., Liu W.Q., Liu Y., Loparco F., Luo C.N., Ma M., Ma P.X., Ma T., Ma X.Y., Marsella G., Mazziotta M.N., Mo D., Niu X.Y., Pan X., Parenti A., Peng W.X., Peng X.Y., Perrina C., Qiao R., Rao J.N., Ruina A., Salinas M.M., Shang G.Z., Shen W.H., Shen Z.Q., Shen Z.T., Silveri L., Song J.X., Stolpovskiy M., Su H., Su M., Sun Z.Y., Surdo A., Teng X.J., Tykhonov A., Wang H., Wang J.Z., Wang L.G., Wang S., Wang X.L., Wang Y., Wang Y.F., Wang Y.Z., Wang Z.M., Wei D.M., Wei J.J., Wei Y.F., Wen S.C., Wu D., Wu J., Wu L.B., Wu S.S., Wu X., Xia Z.Q., Xu H.T., Xu Z.H., Xu Z.L., Xu Z.Z., Xue G.F., Yang H.B., Yang P., Yang Y.Q., Yao H.J., Yu Y.H., Yuan G.W., Yuan Q., Yue C., Zang J.J., Zhang F., Zhang S.X., Zhang W.Z., Zhang Y., Zhang Y.J., Zhang Y.L., Zhang Y.P., Zhang Y.Q., Zhang Z., Zhang Z.Y., Zhao C., Zhao H.Y., Zhao X.F., Zhou C.Y., Zhu Y., Alemanno, F., An, Q., Azzarello, P., Barbato, F. C. T., Bernardini, P., Bi, X. J., Cai, M. S., Catanzani, E., Chang, J., Chen, D. Y., Chen, J. L., Chen, Z. F., Cui, M. Y., Cui, T. S., Cui, Y. X., Dai, H. T., D’Amone, A., De Benedittis, A., De Mitri, I., de Palma, F., Deliyergiyev, M., Di Santo, M., Dong, T. K., Dong, Z. X., Donvito, G., Droz, D., Duan, J. L., Duan, K. K., D’Urso, D., Fan, R. R., Fan, Y. Z., Fang, K., Fang, F., Feng, C. Q., Feng, L., Fusco, P., Gao, M., Gargano, F., Gong, K., Gong, Y. Z., Guo, D. Y., Guo, J. H., Guo, X. L., Han, S. X., Hu, Y. M., Huang, G. S., Huang, X. Y., Huang, Y. Y., Ionica, M., Jiang, W., Kong, J., Kotenko, A., Kyratzis, D., Lei, S. J., Li, S., Li, W. L., Li, X., Li, X. Q., Liang, Y. M., Liu, C. M., Liu, H., Liu, J., Liu, S. B., Liu, W. Q., Liu, Y., Loparco, F., Luo, C. N., Ma, M., Ma, P. X., Ma, T., Ma, X. Y., Marsella, G., Mazziotta, M. N., Mo, D., Niu, X. Y., Pan, X., Parenti, A., Peng, W. X., Peng, X. Y., Perrina, C., Qiao, R., Rao, J. N., Ruina, A., Salinas, M. M., Shang, G. Z., Shen, W. H., Shen, Z. Q., Shen, Z. T., Silveri, L., Song, J. X., Stolpovskiy, M., Su, H., Su, M., Sun, Z. Y., Surdo, A., Teng, X. J., Tykhonov, A., Wang, H., Wang, J. Z., Wang, L. G., Wang, S., Wang, X. L., Wang, Y., Wang, Y. F., Wang, Y. Z., Wang, Z. M., Wei, D. M., Wei, J. J., Wei, Y. F., Wen, S. C., Wu, D., Wu, J., Wu, L. B., Wu, S. S., Wu, X., Xia, Z. Q., Xu, H. T., Xu, Z. H., Xu, Z. L., Xu, Z. Z., Xue, G. F., Yang, H. B., Yang, P., Yang, Y. Q., Yao, H. J., Yu, Y. H., Yuan, G. W., Yuan, Q., Yue, C., Zang, J. J., Zhang, F., Zhang, S. X., Zhang, W. Z., Zhang, Y., Zhang, Y. J., Zhang, Y. L., Zhang, Y. P., Zhang, Y. Q., Zhang, Z., Zhang, Z. Y., Zhao, C., Zhao, H. Y., Zhao, X. F., Zhou, C. Y., and Zhu, Y.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Dark matter, General Physics and Astronomy, chemistry.chemical_element, FOS: Physical sciences, Cosmic ray, Space (mathematics), 01 natural sciences, 7. Clean energy, Cosmic ray, helium, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Energy spectrum, cosmic rays, dark matter, space, crystals, 010306 general physics, Helium, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), COSMIC cancer database, detector, Settore FIS/01 - Fisica Sperimentale, calibration, chemistry, Particle, Astrophysics - High Energy Astrophysical Phenomena, Nucleon, performance
Abstract

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the DArk Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of $4.3\sigma$. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out., Comment: 11 pages, 13 figures, published in Phys. Rev. Lett. Add one more digit for first three columns in Table S2

Published
2021

3. Polycatenate Structure and Thermal Analysis of a New 2D + 2D Cobalt(II) Coordination Polymer Based on 5-Methoxylisophthalic Acid and 3,5-Bis(imidazole-1-yl)pyridine Co-Ligands

Author

Y. F. Wang, J. J. Wei, and X. H. Zhai

Subjects
010405 organic chemistry, Coordination polymer, General Chemical Engineering, chemistry.chemical_element, Infrared spectroscopy, General Chemistry, Triclinic crystal system, 010402 general chemistry, 01 natural sciences, Hydrothermal circulation, 0104 chemical sciences, Crystallography, chemistry.chemical_compound, chemistry, Pyridine, Imidazole, Thermal analysis, Cobalt
Abstract

A new Co(II) compound, namely [Co(CH3O-H2Ip)(Bip)] n (I) (CH3O-H2Ip = 5-methoxylisophthalic acid and Bip = 3,5-bis(imidazole-1-yl)pyridine), has been synthesized through combination of CH3O-H2Ip, Bip and Co(II) acetate under hydrothermal condition and structurally characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction (CIF file CCDC no. 977220). It crystallizes in triclinic, space group P1 with a = 9.764(6), b = 10.106(6), c = 11.673(7) A, α = 104.12970°, β = 100.601(7)°, γ = 105.324(7)°, V = 1038.6(11) A3, C20H16CoN5O5, Mr = 465.31, Z = 2, ρcalcd = 1.488 g/cm3, μ(MoKα) = 0.869 mm−1, F(000) = 476, the final R = 0.0652 and wR = 0.1530. The X-ray analysis demonstrates that compound I exhibits a 2D + 2D polyrotaxane (4, 4) net network. Moreover, the thermal analysis of compound I has also been investigated.

Published
2018
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4. Measurement of the cosmic ray proton spectrum from 40 GeV to 100 TeV with the DAMPE satellite

Author

Chi Wang, Y. Z. Gong, Yujuan Liu, Kai-Kai Duan, Yaohui Zhang, L. G. Wang, Dong Ya Guo, Cihang Luo, X. Y. Peng, Jie Liu, Guangshun Huang, Zhi-Yu Sun, S. Wang, R. R. Fan, Maria Ionica, Jie Kong, Peng-Xiong Ma, Zhi Hui Xu, Xiaoyuan Huang, Yu-Sa Wang, N. H. Liao, L. Feng, Michael Ma, H. Liu, X. Y. Ma, Z. X. Dong, Dingsong Wu, Jun-jun Guo, Niu Xiaoyang, A. D'Amone, K. Gong, S. C. Wen, I. De Mitri, P. Azzarello, Min Gao, Chengrui Zhou, Shengxia Zhang, Shumei Wu, Mn Mazziotta, G. Z. Shang, K. Xi, Xian-Min Jin, F. Loparco, Xin-Fu Zhao, Z. Z. Xu, Y. Y. Huang, Shuang Xue Han, X. L. Wang, Zhongjie Yang, Y. H. Yu, G. Marsella, Zhao-Min Wang, Jinglai Duan, Andrii Tykhonov, S. B. Liu, Y. Zhang, Meng Su, Q. An, Y. F. Dong, C. Q. Feng, Xiulian Pan, Ju-Xian Song, Peidong Yang, W. Li, Y. M. Hu, S.X. Li, S. Y. Ma, H. T. Xu, Jindong Zhang, Z. Q. Xia, Yali Zhou, Jialong Chen, J. Z. Wang, X. X. Li, H. Su, M. S. Cai, Jian Wu, X. J. Bi, Haiqiong Wang, Yifan Yang, Tianxiao Ma, F. J. Gan, Donghong Chen, J. J. Zang, Hao Ting Dai, Huaguang Wang, Zhoubin Zhang, P. Bernardini, Z.-Q. Shen, F. Gargano, H. S. Chen, Manyu Ding, Y. F. Liang, R. Qiao, D. Droz, Chuan Yue, W. X. Peng, Y. F. Wei, Shi-Jun Lei, Q. Yuan, Y. J. Zhang, P. Fusco, Yun-Zhi Zhang, A. Surdo, YM Liang, Jiang Chang, J. J. Wei, Lihui Wu, D. Mo, Y. Li, Giacinto Donvito, A. De Benedittis, Wangli Chen, Yang Haibo, Quan Wang, R. Asfandiyarov, M. Di Santo, J. Y. Zhang, Xi Zhu, J. N. Rao, D. M. Wei, Zongye Zhang, Hong Yun Zhao, Yu-Xuan Zhu, D. D'Urso, Hu-Rong Yao, S. Vitillo, Yen-Po Wang, Yugang Zhang, M. Y. Cui, M. M. Salinas, Fang Fang, Wei Liu, T. S. Cui, Huan Zhao, Z. Xu, X. J. Teng, Tie-Kuang Dong, W. H. Shen, Z. T. Shen, Shanta M. Zimmer, Xian Qiang Li, Xin Wu, C. Liu, Y. F. Wang, V. Gallo, W. Zhang, Wei Jiang, Yuqing Fan, Fengtao Zhang, G. F. Xue, Pengchao Zhang, Xiangpeng Guo, Xixian Wang, An Q., Asfandiyarov R., Azzarello P., Bernardini P., Bi X. J., Cai M. S., Chang J., Chen D. Y., Chen H. F., Chen J. L., Chen W., Cui M. Y., Cui T. S., Dai H. T., D'Amone A., De Benedittis A., De Mitri I., Di Santo M., Ding M., Dong T. K., Dong Y. F., Dong Z. X., Donvito G., Droz D., Duan J. L., Duan K. K., D'Urso D., Fan R. R., Fan Y. Z., Fang F., Feng C. Q., Feng L., Fusco P., Gallo V., Gan F. J., Gao M., Gargano F., Gong K., Gong Y. Z., Guo D. Y., Guo J. H., Guo X. L., Han S. X., Hu Y. M., Huang G. S., Huang X. Y., Huang Y. Y., Ionica M., Jiang W., Jin X., Kong J., Lei S. J., Li S., Li W. L., Li X., Li X. Q., Li Y., Liang Y. F., Liang Y. M., Liao N. H., Liu C. M., Liu H., Liu J., Liu S. B., Liu W. Q., Liu Y., Loparco F., Luo C. N., Ma M., Ma P. X., Ma S. Y., Ma T., Ma X. Y., Marsella G., Mazziotta M. N., Mo D., Niu X. Y., Pan X., Peng W. X., Peng X. Y., Qiao R., Rao J. N., Salinas M. M., Shang G. Z., Shen W. H., Shen Z. Q., Shen Z. T., Song J. X., Su H., Su M., Sun Z. Y., Surdo A., Teng X. J., Tykhonov A., Vitillo S., Wang C., Wang H., Wang H. Y., Wang J. Z., Wang L. G., Wang Q., Wang S., Wang X. H., Wang X. L., Wang Y. F., Wang Y. P., Wang Y. Z., Wang Z. M., Wei D. M., Wei J. J., Wei Y. F., Wen S. C., Wu D., Wu J., Wu L. B., Wu S. S., Wu X., Xi K., Xia Z. Q., Xu H. T., Xu Z. H., Xu Z. L., Xu Z. Z., Xue G. F., Yang H. B., Yang P., Yang Y. Q., Yang Z. L., Yao H. J., Yu Y. H., Yuan Q., Yue C., Zang J. J., Zhang F., Zhang J. Y., Zhang J. Z., Zhang P. F., Zhang S. X., Zhang W. Z., Zhang Y., Zhang Y. J., Zhang Y. L., Zhang Y. P., Zhang Y. Q., Zhang Z., Zhang Z. Y., Zhao H., Zhao H. Y., Zhao X. F., Zhou C. Y., Zhou Y., Zhu X., Zhu Y., Zimmer S., An, Q., Asfandiyarov, R., Azzarello, P., Bernardini, P., Bi, X. J., Cai, M. S., Chang, J., Chen, D. Y., Chen, H. F., Chen, J. L., Chen, W., Cui, M. Y., Cui, T. S., Dai, H. T., D'Amone, A., De Benedittis, A., De Mitri, I., Di Santo, M., Ding, M., Dong, T. K., Dong, Y. F., Dong, Z. X., Donvito, G., Droz, D., Duan, J. L., Duan, K. K., D'Urso, D., Fan, R. R., Fan, Y. Z., Fang, F., Feng, C. Q., Feng, L., Fusco, P., Gallo, V., Gan, F. J., Gao, M., Gargano, F., Gong, K., Gong, Y. Z., Guo, D. Y., Guo, J. H., Guo, X. L., Han, S. X., Hu, Y. M., Huang, G. S., Huang, X. Y., Huang, Y. Y., Ionica, M., Jiang, W., Jin, X., Kong, J., Lei, S. J., Li, S., Li, W. L., Li, X., Li, X. Q., Li, Y., Liang, Y. F., Liang, Y. M., Liao, N. H., Liu, C. M., Liu, H., Liu, J., Liu, S. B., Liu, W. Q., Liu, Y., Loparco, F., Luo, C. N., Ma, M., Ma, P. X., Ma, S. Y., Ma, T., Ma, X. Y., Marsella, G., Mazziotta, M. N., Mo, D., Niu, X. Y., Pan, X., Peng, W. X., Peng, X. Y., Qiao, R., Rao, J. N., Salinas, M. M., Shang, G. Z., Shen, W. H., Shen, Z. Q., Shen, Z. T., Song, J. X., Su, H., Su, M., Sun, Z. Y., Surdo, A., Teng, X. J., Tykhonov, A., Vitillo, S., Wang, C., Wang, H., Wang, H. Y., Wang, J. Z., Wang, L. G., Wang, Q., Wang, S., Wang, X. H., Wang, X. L., Wang, Y. F., Wang, Y. P., Wang, Y. Z., Wang, Z. M., Wei, D. M., Wei, J. J., Wei, Y. F., Wen, S. C., Wu, D., Wu, J., Wu, L. B., Wu, S. S., Wu, X., Xi, K., Xia, Z. Q., Xu, H. T., Xu, Z. H., Xu, Z. L., Xu, Z. Z., Xue, G. F., Yang, H. B., Yang, P., Yang, Y. Q., Yang, Z. L., Yao, H. J., Yu, Y. H., Yuan, Q., Yue, C., Zang, J. J., Zhang, F., Zhang, J. Y., Zhang, J. Z., Zhang, P. F., Zhang, S. X., Zhang, W. Z., Zhang, Y., Zhang, Y. J., Zhang, Y. L., Zhang, Y. P., Zhang, Y. Q., Zhang, Z., Zhang, Z. Y., Zhao, H., Zhao, H. Y., Zhao, X. F., Zhou, C. Y., Zhou, Y., Zhu, X., Zhu, Y., and Zimmer, S.

Subjects
dark matter, cosmic rays, space, Proton, Milky Way, Astrophysics::High Energy Astrophysical Phenomena, Dark matter, FOS: Physical sciences, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Kinetic energy, 01 natural sciences, 0103 physical sciences, 010306 general physics, Nuclear Experiment, Research Articles, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Spectral index, Multidisciplinary, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Settore FIS/01 - Fisica Sperimentale, SciAdv r-articles, Physics::Accelerator Physics, High Energy Physics::Experiment, Astrophysics - High Energy Astrophysical Phenomena, Research Article
Abstract

DAMPE satellite has directly measured the cosmic ray proton spectrum from 40 GeV to 100 TeV and revealed a new feature at about 13.6 TeV., The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 1/2 years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

Published
2019

5. The on-orbit calibration of DArk Matter Particle Explorer

Author

Chang Qing Feng, A. D'Amone, X.Q. Ma, K. Gong, D. Mo, R. Asfandiyarov, G. Ambrosi, Y. M. Hu, Peng-Xiong Ma, Xun Feng Zhao, Zhi Hui Xu, Jinglai Duan, Tianxiao Ma, G. Z. Shang, H. T. Xu, C. Liu, X. Y. Ma, M. Y. Cui, S. C. Wen, Chenchen Wang, J. J. Zang, Deng Yi Chen, Xixian Wang, M. M. Salinas, Niu Xiaoyang, Yaping Wang, Shanta M. Zimmer, J. N. Rao, Haiqiong Wang, Da Ming Wei, Z. Y. Sun, Hao Ting Dai, V. Gallo, Q. An, Peidong Yang, Honglong Wang, D. D’Urso, Yuan Zhu Wang, Xiulian Pan, W. Zhang, I. De Mitri, H. Liu, Yang Haibo, Wei Liang Li, D.L. Zhang, H. S. Chen, Min Gao, Li Bo Wu, A. De Benedittis, Wangli Chen, Xi Zhu, Shuyao Li, X.B. Tian, Paolo Bernardini, J.N. Dong, Sha Wu, Y. Q. Zhang, Hu-Rong Yao, Kai-Kai Duan, Y. F. Wei, Jin Chang, Jiangtao Guo, F. J. Gan, S. Y. Ma, Wei Jiang, Z. Q. Xia, Yifan Yang, L. G. Wang, P. Azzarello, Y. J. Zhang, F. Gargano, Zhenyu Zhang, Maria Ionica, Jie Kong, Y. F. Liang, Yali Zhou, Jing Xing Song, M. Di Santo, Xin Wu, Y. F. Wang, R. R. Fan, R. Qiao, M. Caragiulo, Yuqing Fan, N. H. Liao, Jindan Zhang, Qian Wang, Y.L. Xin, Jie Liu, Zhoubin Zhang, Y. H. Yu, Zhao-Qiang Shen, T. S. Cui, Zhao-Min Wang, Yun Long Zhang, Yao Ming Liang, G. F. Xue, Shengxia Zhang, Zhongjie Yang, J. J. Wei, Z. Xu, Dan Jiang, F. Loparco, Laiyu Zhang, S. Vitillo, X. L. Wang, Wei Liu, Y. Zhang, Yongxiang Liu, J.B. Zhang, J. L. Chen, Qing Yuan, Meng Su, Z.Z. Xu, G. Marsella, Andrii Tykhonov, S. Wang, X. J. Teng, Tie-Kuang Dong, M. M. Ma, Zhang Yalan, Shi-Jun Lei, D. Droz, Fengtao Zhang, Huan Zhao, S. B. Liu, M. N. Mazziotta, H. Su, A. Surdo, Jin Zhou Wang, S. Garrappa, W. H. Shen, Yinlian Zhu, Z. T. Shen, Pengchao Zhang, Guang Shun Huang, Fang Fang, X. X. Li, Hong Yun Zhao, M. S. Cai, W. X. Peng, Y. Li, Y. Z. Gong, Z. X. Dong, Chang Yi Zhou, X. Y. Peng, Lingyan Feng, K. Xi, Jindong Zhang, Di Wu, Jian Wu, Chuan Yue, Y. Y. Huang, P. Fusco, Y. F. Dong, Shan-Shan Gao, Manyu Ding, Xian-Min Jin, Ambrosi, G., An, Q., Asfandiyarov, R., Azzarello, P., Bernardini, P., Cai, M. S., Caragiulo, M., Chang, J., Chen, D. Y., Chen, H. F., Chen, J. L., Chen, W., Cui, M. Y., Cui, T. S., Dai, H. T., D'Amone, A., Benedittis, De, Mitri, De, I., Ding, Di Santo, M., Dong, J. N., Dong, T. K., Dong, Y. F., Dong, Z. X., Droz, D., Duan, K. K., Duan, J. L., D'Urso, D., Fan, R. R., Fan, Y. Z., Iemail, Author, Fang, F., Feng, C. Q., Feng, L., Fusco, P., Gallo, V., Gan, F., Gao, M., Gao, S. S., Gargano, F., Garrappa, S., Gong, K., Gong, Y. Z., Guo, J. H., Email Author, Hu, Y. M., Huang, G. S., Huang, Y. Y., Ionica, M., Jiang, D., Jiang, W., Jin, X., Kong, J., Lei, S. J., Li, S., Li, X., Li, W. L., Li, Y., Liang, Y. F., Liang, Y. M., Liao, N. H., Liu, C. M., Liu, H., Liu, J., Liu, S. B., Liu, W. Q., Liu, Y., Loparco, F., Ma, M., Ma, P. X., Ma, S. Y., Ma, T., Ma, X. Q., Ma, X. Y., Marsella, G., Mazziotta, M. N., Mo, D., Niu, X. Y., Pan, X, Peng, X. Y., Peng, W. X., Qiao, R., Rao, J. N., Salinas, M. M., Shang, G. Z., Shen, W. H., Shen, Z. Q., Shen, Z. T., Song, J. X., Su, H., Su, M., Sun, Z. Y., Surdo, A., Teng, X. J., Tian, X. B., Tykhonov, A., Vitillo, S., Wang, C., Wang, H., Wang, H. Y., Wang, J. Z., Wang, L. G., Wang, Q., Wang, S., Wang, X. H., Wang, X. L., Wang, Y. F., Wang, Y. P., Wang, Y. Z., Wang, Z. M., Wen, S. C., Wei, D. M., Wei J. J., A, Wei Y. F., C, Wu D., J, Wu J., A, H, Wu, L. B., c Wu, S. S., k Wu, X., d Xi, K., j Xia, Z. Q., a h, Xin Y. L., A, Xu H. T., K, Xu Z. H., A, H, Xu, Z. L., a Xu, Z. Z., a Xue, G. F., k Yang, H. B., j Yang, P., j Yang, Y. Q., j Yang, Z. L., j Yao, H. J., j Yu, Y. H., j Yuan, Q., a h, Yue C., A, Zang J. J., A, Zhang D. L., C, Zhang F., M, Zhang J. B., C, Zhang J. Y., M, Zhang J. Z., J, Zhang L., A, I, Zhang, P. F., a Zhang, S. X., j Zhang, W. Z., k Zhang, Y., a i, Zhang Y. J., J, Zhang Y. Q., A, Y. L., c Zhang, Y. P., j Zhang, Z., a Zhang, Z. Y., c Zhao, H., m Zhao, H. Y., j Zhao, X. F., k Zhou, C. Y., k Zhou, Y., j Zhu, X., c Zhu, Y., k Zimmer, Ambrosi G., An Q., Asfandiyarov R., Azzarello P., Bernardini P., Cai M. S., Caragiulo M., Chang J., Chen D. Y., Chen H. F., Chen J. L., Chen W., Cui M. Y., Cui T. S., Dai H. T., D'Amone A., De Beneditti, De Mitri, I. Ding, Dong J. N., Dong T. K., Dong Y. F., Dong Z. X., Droz D., Duan K. K., Duan J. L., D'Urso D., Fan R. R., Fan Y. Z., iEmail Author, Fang F., Feng C. Q., Feng L., Fusco P., Gallo V., Gan F., Gao M., Gao S. S., Gargano F., Garrappa S., Gong K., Gong Y. Z., J. H. Email Author, Hu Y. M., Huang G. S., Huang Y. Y., Ionica M., Jiang D., Jiang W., Jin X., Kong J., Lei S. J., Li S., Li X., Li W. L., Li Y., Liang Y. F., Liang Y. M., Liao N. H., Liu C. M., Liu H., Liu J., Liu S. B., Liu W. Q., Liu Y., Loparco F., Ma M., Ma P. X., Ma S. Y., Ma T., Ma X. Q., Ma X. Y., Marsella G., Mazziotta M. N., Mo D., Niu X. Y., Pan X, Peng X. Y., Peng W. X., Qiao R., Rao J. N., Salinas M. M., Shang G. Z., Shen W. H., Shen Z. Q., Shen Z. T., Song J. X., Su H., Su M., Sun Z. Y., Surdo A., Teng X. J., Tian X. B., Tykhonov A., Vitillo S., Wang C., Wang H., Wang H. Y., Wang J. Z., Wang L. G., Wang Q., Wang S., Wang X. H., Wang X. L., Wang Y. F., Wang Y. P., Wang Y. Z., Wang Z. M., Wen S. C., Wei D. M., Wei J. J. a, Wei Y. F. c, Wu D. j, Wu J. a, h Wu, L. B. c Wu, S. S. k Wu, X. d Xi, K. j Xia, Z. Q. a h, Xin Y. L. a, Xu H. T. k, Xu Z. H. a, h Xu, Z. L. a Xu, Z. Z. a Xue, G. F. k Yang, H. B. j Yang, P. j Yang, Y. Q. j Yang, Z. L. j Yao, H. J. j Yu, Y. H. j Yuan, Q. a h, Yue C. a, Zang J. J. a, Zhang D. L. c, Zhang F. m, Zhang J. B. c, Zhang J. Y. m, Zhang J. Z. j, Zhang L. a, i Zhang, P. F. a Zhang, S. X. j Zhang, W. Z. k Zhang, Y. a i, Zhang Y. J. j, Zhang Y. Q. a, Y. L. c Zhang, Y. P. j Zhang, Z. a Zhang, Z. Y. c Zhao, H. m Zhao, H. Y. j Zhao, X. F. k Zhou, C. Y. k Zhou, Y. j Zhu, X. c Zhu, and Y. k Zimmer

Subjects
Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Dark matter, FOS: Physical sciences, Cosmic ray, Scintillator, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Neutron detection, Dark Matter, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Calorimeter (particle physics), 010308 nuclear & particles physics, Detector, Settore FIS/01 - Fisica Sperimentale, Gamma ray, Astronomy, Astronomy and Astrophysics, Cosmic Rays, South Atlantic Anomaly, High Energy Physics::Experiment, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

The DArk Matter Particle Explorer (DAMPE), a satellite-based cosmic ray and gamma-ray detector, was launched on December 17, 2015, and began its on-orbit operation on December 24, 2015. In this work we document the on-orbit calibration procedures used by DAMPE and report the calibration results of the Plastic Scintillator strip Detector (PSD), the Silicon-Tungsten tracKer-converter (STK), the BGO imaging calorimeter (BGO), and the Neutron Detector (NUD). The results are obtained using Galactic cosmic rays, bright known GeV gamma-ray sources, and charge injection into the front-end electronics of each sub-detector. The determination of the boundary of the South Atlantic Anomaly (SAA), the measurement of the live time, and the alignments of the detectors are also introduced. The calibration results demonstrate the stability of the detectors in almost two years of the on-orbit operation.

Published
2019

6. Geometrical reconstruction of fluorescence events observed by the LHAASO experiment *

Author

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

Subjects
Physics, Nuclear and High Energy Physics, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, business.industry, Astrophysics::High Energy Astrophysical Phenomena, Detector, Resolution (electron density), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Cosmic ray, 01 natural sciences, Fluorescence, law.invention, Telescope, Optics, law, 0103 physical sciences, Trajectory, Range (statistics), 010306 general physics, business, Instrumentation, Cherenkov radiation
Abstract

The LHAASO-WFCTA experiment, which aims to observe cosmic rays in the sub-EeV range using the fluorescence technique, uses a new generation of high-performance telescopes. To ensure that the experiment has excellent detection capability associated with the measurement of the energy spectrum, the primary composition of cosmic rays, and so on, an accurate geometrical reconstruction of air-shower events is fundamental. This paper describes the development and testing of geometrical reconstruction for stereo viewed events using the WFCTA (Wide Field of view Cherenkov/Fluorescence Telescope Array) detectors. Two approaches, which take full advantage of the WFCTA detectors, are investigated. One is the stereo-angular method, which uses the pointing of triggered SiPMs in the shower trajectory, and the other is the stereo-timing method, which uses the triggering time of the fired SiPMs. The results show that both methods have good geometrical resolution; the resolution of the stereo-timing method is slightly better than the stereo-angular method because the resolution of the latter is slightly limited by the shower track length.

Published
2021
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7. Observation of the Crab Nebula with LHAASO-KM2A − a performance study *

Author

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

Subjects
Physics, Nuclear and High Energy Physics, High energy, 010308 nuclear & particles physics, Cosmic distance ladder, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Crab Nebula, 0103 physical sciences, Energy spectrum, 010306 general physics, Instrumentation, Energy (signal processing)
Abstract

A sub-array of the Large High Altitude Air Shower Observatory (LHAASO), KM2A is mainly designed to observe a large fraction of the northern sky to hunt for γ-ray sources at energies above 10 TeV. Even though the detector construction is still underway, half of the KM2A array has been operating stably since the end of 2019. In this paper, we present the KM2A data analysis pipeline and the first observation of the Crab Nebula, a standard candle in very high energy γ-ray astronomy. We detect γ-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 0.05 0.08 ) 10 (E/20 TeV) cm s TeV . It is consistent with previous measurements by other experiments. This opens a new window of γ-ray astronomy above 0.1 PeV through which new ultrahigh-energy γ-ray phenomena, such as cosmic PeVatrons, might be discovered.

Published
2021
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8. The altitudinal effects on photosynthesis of Rosa platyacantha from the Tianshan Mountains in Northwestern China

Author

H. Ge, S. H. Yang, and J. J. Wei

Subjects
0106 biological sciences, 0301 basic medicine, education.field_of_study, Antioxidant, Physiology, medicine.medical_treatment, Population, Plant physiology, Plant Science, Biology, Noon, Photosynthesis, 01 natural sciences, Enzyme assay, Lipid peroxidation, 03 medical and health sciences, chemistry.chemical_compound, 030104 developmental biology, chemistry, Botany, biology.protein, medicine, education, Chlorophyll fluorescence, 010606 plant biology & botany
Abstract

The altitudinal effects on photosynthesis were measured on progenies of three populations of Rosa platyacantha Schrenk from altitudes of 1,170 (L); 1,580 (M); and 1,920 (H) m a. s. l. During the day, net photosynthetic rate (P N) decreased in all populations due to the high air temperature in the summer. The H population showed a significantly lower P N at noon compared to other populations. The midday depression of P N occurred in L and M populations due to stomatal limitations, while P N inhibition was associated with PSII activity decline in the H population. In order to avoid photodamage, the plants of H population triggered active antioxidant defenses with a higher enzyme activity and redox ratio of ascorbate at midday compared to the L and M populations. However, more oxidative injury still occurred in the H plants at noon due to higher lipid peroxidation. Our results indicated that the provenance significantly affected photosynthesis in R. platyacantha from northwestern China.

Published
2016
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9. Collective Surface Plasmon Resonances in Two-Dimensional Assemblies of Au and Ag Nanocrystals: Experiments and Discrete Dipole Approximation Simulation

Author

Peng Yang, Marie-Paule Pileni, Pierre-Antoine Albouy, Hervé Portalès, and J. J. Wei

Subjects
Coupling, Materials science, Absorption spectroscopy, Surface plasmon, Analytical chemistry, 02 engineering and technology, Discrete dipole approximation, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Molecular physics, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, General Energy, Nanocrystal, Absorption band, Physical and Theoretical Chemistry, Surface plasmon resonance, 0210 nano-technology, Anisotropy
Abstract

The UV–visible absorption spectra of two-dimensional (2D) assemblies of Ag or Au nanocrystals (NCs) are measured in transmission at variable incidence angles for different average NC diameters ranging from 7.0 to 3.9 nm. The absorption spectra dominated by the collective surface plasmon resonance (SPR) absorption band are compared to those calculated using the discrete dipole approximation (DDA) method. The anisotropy of the optical response is inherent to the planar geometry of the NC assembly because of the near-field coupling between nanocrystals. For Ag NCs, the absorption spectra reveal the splitting of the SPR band into two components, namely, the transverse and longitudinal modes. At variance, no SPR band splitting is observed for 2D assemblies of Au NCs with identical size and coating agent. These features were satisfactorily reproduced by DDA simulation even though the SPR mode energies deduced from our calculations slightly overestimate the measured ones. The influence of the coating dodecanethi...

Published
2016
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10. ALTERNATIVE TO FOUR-COMPONENT DECOMPOSITION FOR POLARIMETRIC SAR

Author

Z. Zhao, G. M. Huang, J. J. Wei, and Jian Zhang

Subjects
lcsh:Applied optics. Photonics, Physics, Similarity (geometry), 010504 meteorology & atmospheric sciences, lcsh:T, Scattering, business.industry, Mathematical analysis, 0211 other engineering and technologies, Polarimetry, lcsh:TA1501-1820, 02 engineering and technology, Dihedral angle, lcsh:Technology, 01 natural sciences, Power (physics), Orientation (vector space), Matrix (mathematics), Optics, lcsh:TA1-2040, lcsh:Engineering (General). Civil engineering (General), business, Eigendecomposition of a matrix, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences
Abstract

There are more unknowns than equations to solve for previous four-component decomposition methods. In this case, the nonnegative power of each scattering mechanism has to be determined with some assumptions and physical power constraints. This paper presents a new decomposition scheme, which models the measured matrix after polarimetric orientation angle (POA) compensation as a linear sum of five scattering mechanisms (i.e., odd-bounce scattering, double-bounce scattering, diffuse scattering, volume scattering, and helix scattering). And the volume scattering power is calculated by a slight modified NNED method, owing to this method considering the external volume scattering model from oblique dihedral structure. After the helix and volume scattering powers have been determined sequentially, the other three scattering powers are estimated by combining the generalized similarity parameter (GSP) and the eigenvalue decomposition. Among them, due to POA compensation, the diffuse scattering induced from a dihedral with a relative orientation of 45º has negligible scattering power. Thus, the new method can be reduced as four-component decomposition automatically. And then the ALOS-2 PolSAR data covering Guiyang City, Guizhou Province, China were used to evaluate the performance of the new method in comparison with some classical decomposition methods (i.e. Y4R, S4R and G4U).

Published
2016
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11. The DArk Matter Particle Explorer mission

Author

M. M. Ma, Y.L. Xin, Shengxia Zhang, Y. Y. Huang, Y. Z. Gong, H.Y. Zhao, P. Fusco, Zhao-Qiang Shen, Peidong Yang, Zhao-Min Wang, Yuan Zhu Wang, Maria Ionica, Jie Kong, Yun Long Zhang, F. Loparco, Dan Jiang, J.N. Dong, Y. L. Li, X. Y. Peng, J. L. Chen, H. S. Chen, S. C. Wen, Y. F. Dong, Jinglai Duan, P. Azzarello, N. H. Liao, X. L. Wang, M. M. Salinas, M. Caragiulo, Ya Peng Zhang, M. Pohl, V. Gallo, W. Zhang, Andrii Tykhonov, Niu Xiaoyang, Hai Tao Xu, X. X. Li, Shi-Jun Lei, G. Marsella, Wei Jiang, Min Gao, M. S. Cai, X. Zhu, Z. X. Dong, Yong Zhou, S. Y. Ma, Wei Liang Li, A. De Benedittis, Q. An, Sha Wu, Deng Yi Chen, Y. F. Wei, J.B. Zhang, T.T. Miao, G. F. Xue, Chuan Yue, Z.L. Yang, Y.F. Liang, P. Bernardini, Yifan Yang, Laiyu Zhang, Jianyi Yang, W. X. Peng, Z. M. Zhang, Giacinto Donvito, L. G. Wang, J. G. Lu, Y. J. Zhang, R. Qiao, Shan-Shan Gao, Zi-Qing Xia, Hui Jun Yao, Zhi-Yu Sun, Fang Fang, Yi-Zhong Fan, S. Vitillo, Jie Liu, S. Li, J. J. Wei, R. R. Fan, Lei Feng, Y. Zhu, K. Xi, A. D'Amone, Peng-Xiong Ma, Ping Zhang, Xun Feng Zhao, Jianli Zhang, M. N. Mazziotta, H. Su, Di Wu, Y. M. Hu, Da Ming Wei, Chang Yi Zhou, A. Surdo, Yang Liu, Yen-Po Wang, D. Droz, D. D'Urso, W. Chen, Jian Wu, Jin Zhou Wang, F. Zhang, Q. Wang, Jian Hua Guo, M. Duranti, X. J. Teng, Tie-Kuang Dong, I. De Mitri, Xiao Yong Ma, W. H. Shen, X.B. Tian, Chao Zhang, Z. T. Shen, Hong Yun Zhao, Z. Xu, Chang Qing Feng, T. S. Cui, Chunjie Wang, Ju-Xian Song, G. Ambrosi, Q.Z. Liu, Xiaohui Wang, Haiyan Wang, Y. Zhang, X.Q. Ma, Meng Su, D. Mo, Yan Fang Wang, R. Asfandiyarov, Yao Ming Liang, B. Bertucci, Stephan Zimmer, Guang Shun Huang, Yang Haibo, X. Jin, Zhenyu Zhang, M. Di Santo, Tao Ma, Xin Wu, M. Y. Cui, Yongjie Zhang, Yu-Hong Yu, H. Liu, J. N. Rao, Qiang Yuan, S. B. Liu, Jilong Zhang, Chi Wang, W.Q. Gan, Wenqiang Liu, V. Vagelli, Zi Zong Xu, Jin Chang, F. J. Gan, F. Gargano, D.L. Zhang, H. W. Wang, Kai-Kai Duan, K. Gong, G. Z. Shang, Shu Xin Wang, J. J. Zang, Chang, J., Ambrosi, G., An, Q., Asfandiyarov, R., Azzarello, P., Bernardini, P., Bertucci, B., Cai, M. S., Caragiulo, M., Chen, D. Y., Chen, H. F., Chen, J. L., Chen, W., Cui, M. Y., Cui, T. S., D'Amone, A., DE BENEDITTIS, Antonio, De Mitri, I., DI SANTO, Margherita, Dong, J. N., Dong, T. K., Dong, Y. F., Dong, Z. X., Donvito, G., Droz, D., Duan, K. K., Duan, J. L., Duranti, M., D'Urso, D., Fan, R. R., Fan, Y. Z., Fang, F., Feng, C. Q., Feng, L., Fusco, P., Gallo, V., Gan, F. J., Gan, W. Q., Gao, M., Gao, S. S., Gargano, F., Gong, K., Gong, Y. Z., Guo, J. H., Hu, Y. M., Huang, G. S., Huang, Y. Y., Ionica, M., Jiang, D., Jiang, W., Jin, X., Kong, J., Lei, S. J., Li, S., Li, X., Li, W. L., Li, Y., Liang, Y. F., Liang, Y. M., Liao, N. H., Liu, Q. Z., Liu, H., Liu, J., Liu, S. B., Liu, W. Q., Liu, Y., Loparco, F., Lã¼, J., Ma, M., Ma, P. X., Ma, S. Y., Ma, T., Ma, X. Q., Ma, X. Y., Marsella, G., Mazziotta, M. N., Mo, D., Miao, T. T., Niu, X. Y., Pohl, M., Peng, X. Y., Peng, W. X., Qiao, R., Rao, J. N., Salinas, M. M., Shang, G. Z., Shen, W. H., Shen, Z. Q., Shen, Z. T., Song, J. X., Su, H., Su, M., Sun, Z. Y., Surdo, A., Teng, X. J., Tian, X. B., Tykhonov, A., Vagelli, V., Vitillo, S., Wang, C., Wang, Chi, Wang, H., Wang, H. Y., Wang, J. Z., Wang, L. G., Wang, Q., Wang, S., Wang, X. H., Wang, X. L., Wang, Y. F., Wang, Y. P., Wang, Y. Z., Wen, S. C., Wang, Z. M., Wei, D. M., Wei, J. J., Wei, Y. F., Wu, D., Wu, J., Wu, S. S., Wu, X., Xi, K., Xia, Z. Q., Xin, Y. L., Xu, H. T., Xu, Z. L., Xu, Z. Z., Xue, G. F., Yang, H. B., Yang, J., Yang, P., Yang, Y. Q., Yang, Z. L., Yao, H. J., Yu, Y. H., Yuan, Q., Yue, C., Zang, J. J., Zhang, C., Zhang, D. L., Zhang, F., Zhang, J. B., Zhang, J. Y., Zhang, J. Z., Zhang, L., Zhang, P. F., Zhang, S. X., Zhang, W. Z., Zhang, Y., Zhang, Y. J., Zhang, Y. Q., Zhang, Y. L., Zhang, Y. P., Zhang, Z., Zhang, Z. Y., Zhao, H., Zhao, H. Y., Zhao, X. F., Zhou, C. Y., Zhou, Y., Zhu, X., Zhu, Y., Zimmer, S., DE BENEDITTIS, ANTONIO, DI SANTO, MARGHERITA, and Lü, J.

Subjects
Physics - Instrumentation and Detectors, Satellite launches, Gamma ray observatories, Astrophysics, Galactic cosmic rays, 01 natural sciences, Cosmology, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), Observatory, Detectors and Experimental Techniques, Cosmic rays , dark matter , space experiments, 010303 astronomy & astrophysics, physics.ins-det, Space science missions, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, Astrophysics::Instrumentation and Methods for Astrophysics, Instrumentation and Detectors (physics.ins-det), Cosmology, Galaxies, Gamma rays, Tellurium compounds, Chinese Academy of Sciences, Dark matter particles, Explorer missions, Galactic cosmic rays, Gamma ray observatories, Satellite launches, Scientific objectives, Space science missions, Cosmic rays, Space Science, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Particle Physics - Experiment, Astrophysics and Astronomy, Astrophysics::High Energy Astrophysical Phenomena, Dark matter, FOS: Physical sciences, Cosmic ray, dark matter, Tellurium compounds, 0103 physical sciences, Cosmic rays, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010308 nuclear & particles physics, hep-ex, Gamma rays, Astronomy, Astronomy and Astrophysics, Galaxies, Chinese academy of sciences, Galaxy, Scientific objectives, Dark matter particles, Chinese Academy of Sciences, Satellite, space experiments, Explorer missions, astro-ph.IM
Abstract

The DArk Matter Particle Explorer (DAMPE), one of the four scientific space science missions within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Sciences, is a general purpose high energy cosmic-ray and gamma-ray observatory, which was successfully launched on December 17th, 2015 from the Jiuquan Satellite Launch Center. The DAMPE scientific objectives include the study of galactic cosmic rays up to $\sim 10$ TeV and hundreds of TeV for electrons/gammas and nuclei respectively, and the search for dark matter signatures in their spectra. In this paper we illustrate the layout of the DAMPE instrument, and discuss the results of beam tests and calibrations performed on ground. Finally we present the expected performance in space and give an overview of the mission key scientific goals., 45 pages, including 29 figures and 6 tables. Published in Astropart. Phys

Published
2017

12. Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons

Author

J. N. Rao, D. M. Wei, P. Azzarello, Peng-Xiong Ma, Y. H. Yu, Shan-Shan Gao, Chi Wang, Q. An, L. G. Wang, YM Liang, Dong Ya Guo, Min Gao, Z. X. Dong, Jie Liu, Tianxiao Ma, Donghong Chen, Wei Liu, Yifan Yang, Zhihua Zhang, Jun-jun Guo, Y. F. Liang, S. Wang, Huan Zhao, D.L. Zhang, X.Q. Ma, Maria Ionica, Jie Kong, G. Ambrosi, Luzhao Feng, Yu-Sa Wang, Fang Fang, N. H. Liao, D. Mo, Niu Xiaoyang, Yaping Wang, R. Qiao, Qiuju Yuan, I. De Mitri, X.B. Tian, Z. Z. Xu, Zheng Wang, Michael Ma, R. Asfandiyarov, X. X. Li, Y. M. Hu, M. S. Cai, Guangshun Huang, M. Di Santo, H. Liu, J.N. Dong, Z.-Q. Shen, Zhongjie Yang, W. X. Peng, Peidong Yang, Jialong Chen, Stephan Zimmer, Y. F. Wei, K. Xi, Laiyu Zhang, Zhi-Yu Sun, W. Li, F. Loparco, X. L. Wang, Chao Zhang, Y. J. Zhang, Y. Z. Gong, Jindong Zhang, X. Y. Ma, M. Duranti, Kai-Kai Duan, Y. Zhang, Yun-Zhi Zhang, R. R. Fan, Valerio Vagelli, Xixian Wang, Ju-Xian Song, G. Marsella, Meng Su, Yaohui Zhang, Xian-Min Jin, S.X. Li, S. B. Liu, Huijun Yao, Andrii Tykhonov, J. J. Wei, Lihui Wu, X. Y. Peng, H. T. Xu, Yujuan Liu, Hong Yun Zhao, Jie Zhang, S. Y. Ma, Z. Q. Xia, Dan Jiang, Yali Zhou, X. J. Teng, Tie-Kuang Dong, S. C. Wen, Y. Li, A. D'Amone, Yi-Zhong Fan, K. Gong, J. Z. Wang, Yugang Zhang, H. S. Chen, Chengrui Zhou, Giacinto Donvito, Yang Haibo, Zhoubin Zhang, P. Bernardini, W. H. Shen, M. Y. Cui, G. Z. Shang, Chuan Yue, Jindan Zhang, Di Wu, Xin-Fu Zhao, Y. Y. Huang, Z. T. Shen, Qian Wang, P. Fusco, Shumei Wu, J. J. Zang, Y. F. Dong, Jinfei Wu, C. Q. Feng, Jinglai Duan, Huaguang Wang, B. Bertucci, Jin Chang, F. J. Gan, F. Gargano, M. N. Mazziotta, H. Su, Haiqiong Wang, Fengtao Zhang, Z. Xu, Pengchao Zhang, Xin Wu, Y. F. Wang, S. Vitillo, D. Droz, T. S. Cui, V. Gallo, W. Zhang, Wei Jiang, G. F. Xue, S. Garrappa, Yu-Xuan Zhu, D. D'Urso, Shi-Jun Lei, M. M. Salinas, Y.L. Xin, Xi Zhu, Shengxia Zhang, A. Surdo, A. De Benedittis, Wangli Chen, Ambrosi, G., An, Q., Asfandiyarov, R., Azzarello, P., Bernardini, P., Bertucci, B., Cai, M. S., Chang, J., Chen, D. Y., Chen, H. F., Chen, J. L., Chen, W., Cui, M. Y., Cui, T. S., D’Amone, A., De Benedittis, A., De Mitri, I., Di Santo, M., Dong, J. N., Dong, T. K., Dong, Y. F., Dong, Z. X., Donvito, G., Droz, D., Duan, K. K., Duan, J. L., Duranti, M., D’Urso, D., Fan, R. R., Fan, Y. Z., Fang, F., Feng, C. Q., Feng, L., Fusco, P., Gallo, V., Gan, F. J., Gao, M., Gao, S. S., Gargano, F., Garrappa, S., Gong, K., Gong, Y. Z., Guo, D. Y., Guo, J. H., Hu, Y. M., Huang, G. S., Huang, Y. Y., Ionica, M., Jiang, D., Jiang, W., Jin, X., Kong, J., Lei, S. J., Li, S., Li, X., Li, W. L., Li, Y., Liang, Y. F., Liang, Y. M., Liao, N. H., Liu, H., Liu, J., Liu, S. B., Liu, W. Q., Liu, Y., Loparco, F., Ma, M., Ma, P. X., Ma, S. Y., Ma, T., Ma, X. Q., Ma, X. Y., Marsella, G., Mazziotta, M. N., Mo, D., Niu, X. Y., Peng, X. Y., Peng, W. X., Qiao, R., Rao, J. N., Salinas, M. M., Shang, G. Z., H. Shen, W., Shen, Z. Q., Shen, Z. T., Song, J. X., Su, H., Su, M., Sun, Z. Y., Surdo, A., Teng, X. J., Tian, X. B., Tykhonov, A., Vagelli, V., Vitillo, S., Wang, C., Wang, H., Wang, H. Y., Wang, J. Z., Wang, L. G., Wang, Q., Wang, S., Wang, X. H., Wang, X. L., Wang, Y. F., Wang, Y. P., Wang, Y. Z., Wen, S. C., Wang, Z. M., Wei, D. M., Wei, J. J., Wei, Y. F., Wu, D., Wu, J., Wu, L. B., Wu, S. S., Wu, X., Xi, K., Xia, Z. Q., Xin, Y. L., Xu, H. T., Xu, Z. L., Xu, Z. Z., Xue, G. F., Yang, H. B., Yang, P., Yang, Y. Q., Yang, Z. L., Yao, H. J., Yu, Y. H., Yuan, Q., Yue, C., Zang, J. J., Zhang, C., Zhang, D. L., Zhang, F., Zhang, J. B., Zhang, J. Y., Zhang, J. Z., Zhang, L., Zhang, P. F., Zhang, S. X., Zhang, W. Z., Zhang, Y., Zhang, Y. J., Zhang, Y. Q., Zhang, Y. L., Zhang, Y. P., Zhang, Z., Zhang, Z. Y., Zhao, H., Zhao, H. Y., Zhao, X. F., Zhou, C. Y., Zhou, Y., Zhu, X., Zhu, Y., and Zimmer, S.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Dark matter, FOS: Physical sciences, Cosmic ray, Electron, 01 natural sciences, dark matter, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), Positron, cosmic rays, 0103 physical sciences, 010303 astronomy & astrophysics, Cherenkov radiation, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, cosmic rays , dark matter , electrons , space experiments, Multidisciplinary, Annihilation, 010308 nuclear & particles physics, Settore FIS/01 - Fisica Sperimentale, Spectrum (functional analysis), electrons, Galaxy, High Energy Physics - Phenomenology, High Energy Physics::Experiment, space experiments, Astrophysics - High Energy Astrophysical Phenomena
Abstract

High energy cosmic ray electrons plus positrons (CREs), which lose energy quickly during their propagation, provide an ideal probe of Galactic high-energy processes and may enable the observation of phenomena such as dark-matter particle annihilation or decay. The CRE spectrum has been directly measured up to $\sim 2$ TeV in previous balloon- or space-borne experiments, and indirectly up to $\sim 5$ TeV by ground-based Cherenkov $\gamma$-ray telescope arrays. Evidence for a spectral break in the TeV energy range has been provided by indirect measurements of H.E.S.S., although the results were qualified by sizeable systematic uncertainties. Here we report a direct measurement of CREs in the energy range $25~{\rm GeV}-4.6~{\rm TeV}$ by the DArk Matter Particle Explorer (DAMPE) with unprecedentedly high energy resolution and low background. The majority of the spectrum can be properly fitted by a smoothly broken power-law model rather than a single power-law model. The direct detection of a spectral break at $E \sim0.9$ TeV confirms the evidence found by H.E.S.S., clarifies the behavior of the CRE spectrum at energies above 1 TeV and sheds light on the physical origin of the sub-TeV CREs., Comment: 18 pages, 6 figures, Nature in press, doi:10.1038/nature24475

Published
2017

13. First Report of Sugarcane Leaf Chlorotic Streak Disease Caused by Xanthomonas sacchari in Guangxi, China

Author

H. Zhou, J. J. Wei, H. J. Sun, Muqing Zhang, Y. S. Li, Govind Pratap Rao, Y. P. Cui, R. Z. Yang, Yixue Bao, and Y. Z. Huang

Subjects
0106 biological sciences, 0301 basic medicine, 03 medical and health sciences, 030104 developmental biology, Botany, Streak, Plant Science, Biology, 01 natural sciences, Agronomy and Crop Science, Xanthomonas sacchari, 010606 plant biology & botany
Published
2017
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14. A major reorganization of Asian climate regime by the early Miocene

Author

Z. T. Guo, B. Sun, Z. S. Zhang, S. Z. Peng, G. Q. Xiao, J. Y. Ge, Q. Z. Hao, Y. S. Qiao, M. Y. Liang, J. F. Liu, Q. Z. Yin, J. J. Wei, Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Shandong Geological Sciences Institute, Shandong Academy of Sciences (SDAS), Nansen-Zhu International Research Center (NZC), Institute of Atmospheric Physics [Beijing] (IAP), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences [Xi’an], and EGU, Publication

Subjects
010504 meteorology & atmospheric sciences, 13. Climate action, [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 15. Life on land, 010502 geochemistry & geophysics, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, 01 natural sciences, [SDU.ENVI] Sciences of the Universe [physics]/Continental interfaces, environment, 0105 earth and related environmental sciences
Abstract

International audience; The global climate system has experienced a series of drastic changes during the Cenozoic. These include the climate transformation in Asia, from a zonal pattern to a monsoon-dominant pattern, the disappearance of subtropical aridity related to a planetary circulation system and the onset of inland deserts in central Asia. Despite of the major advances in the last two decades in characterizing and understanding these climate phenomena, disagreements persist relative to the timing, behaviors and underlying causes. This paper addresses these issues mainly based on two lines of evidence. Firstly, we newly collected the available Cenozoic geological indicators of environment in China to compile the paleoenvironmental maps of ten intervals with a more detailed examination within the Oligocene and Miocene. In confirming the earlier observation that a zonal climate pattern was transformed into a monsoonal one, the new maps within the Miocene indicate that this major change was achieved by the early Miocene, roughly consistent with the onset of loess deposition in China. Although a monsoon-like regime would have existed in the Eocene, it was restricted in the tropical-subtropical regions. The observed latitudinal oscillations of the climate zones during the Paleogene are likely attributable to the imbalanced evolution of polar ice-sheets between the two hemispheres. Secondly, we examine the relevant depositional and soil-forming processes of the Miocene loess-soil sequences to determine the circulation characteristics with special emphasis given to the early Miocene. Continuous eolian deposition in the middle reaches of the Yellow River since the early Miocene firmly indicates the formation of inland deserts, which has been constantly maintained in the past 22 Ma. Inter-section grain-size gradients indicate northerly dust-carrying winds and source location, as is regarded as the main criteria of the Asian winter monsoon system. Meanwhile, the well-developed Luvisols evidence the existence of circulations from the ocean, which brought moisture to northern China. These imply the coexistence of two kinds of circulations, one from the ocean as moisture carrier and another from the inland deserts as dust transporter. The accretionary properties of the early Miocene paleosols, resulted from interactive soil-forming and dust deposition processes, evidence two seasonally alternative circulations, i.e. a monsoonal climate regime. The much stronger development of the early Miocene soils compared to those in the Quaternary loess indicates significantly stronger summer monsoons. These lines of evidence indicate a joint change in circulations and inland aridity by the early Miocene, and suggest a dynamic linkage of them. Our recent numerical experiments reconfirm the potential roles of Tibetan uplift and Paratethys shrinkage in triggering this major climate reorganization, as revealed in peer studies, but yielded more details about their combined scenarios. These two factors would have coacted with the help of South China Sea spreading. Although the realistic effects of each factor remain to be further discriminated, probably through more paleoaltimetrical and tectonic approaches, the Miocene loess record provides a vital insight that tectonics had evolved to a threshold by the early Miocene to cause this major climate reorganization in Asia.

Published
2008

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