Author: "Zhao, X. -F." - Searchworks@Jio Institute Digital Library Search Results

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468 results on '"Zhao, X. -F."'

1. Extragalactic fast X-ray transient from a weak relativistic jet associated with a Type Ic-BL supernova

Author: Sun, H., Li, W. -X., Liu, L. -D., Gao, H., Wang, X. -F., Yuan, W., Zhang, B., Filippenko, A. V., Xu, D., An, T., Ai, S., Brink, T. G., Liu, Y., Liu, Y. -Q., Wang, C. -Y., Wu, Q. -Y., Wu, X. -F., Yang, Y., Zhang, B. -B., Zheng, W. -K., Ahumada, T., Dai, Z. -G., Delaunay, J., Elias-Rosa, N., Benetti, S., Fu, S. -Y., Howell, D. A., Huang, Y. -F., Kasliwal, M. M., Karambelkar, V., Stein, R., Lei, W. -H., Lian, T. -Y., Peng, Z. -K., Ridnaia, A. V., Svinkin, D. S., Wang, X. -Y., Wang, A. -L., Wei, D. -M., An, J., Andrews, M., Bai, J. -M, Dai, C. -Y., Ehgamberdiev, S. A., Fan, Z., Farah, J., Feng, H. -C., Fynbo, J. P. U., Guo, W. -J., Guo, Z., Hu, M. -K., Hu, J. -W., Jiang, S. -Q., Jin, J. -J., Li, A., Li, J. -D., Li, R. -Z., Liang, Y. -F., Ling, Z. -X., Liu, X., Mao, J. -R., McCully, C., Mirzaqulov, D., Newsome, M., Gonzalez, E. Padilla, Pan, X., Terreran, G., Tinyanont, S., Wang, B. -T., Wang, L. -Z., Wen, X. -D., Xiang, D. -F., Xue, S. -J., Yang, J., Zhu, Z. -P., Cai, Z. -M., Castro-Tirado, A. J., Chen, F. -S., Chen, H. -L., Chen, T. -X., Chen, W., Chen, Y. -H., Chen, Y. -F., Chen, Y., Cheng, H. -Q., Cordier, B., Cui, C. -Z., Cui, W. -W., Dai, Y. -F., Fan, D. -W., Feng, H., Guan, J., Han, D. -W., Hou, D. -J., Hu, H. -B., Huang, M. -H., Huo, J., Jia, S. -M., Jia, Z. -Q., Jiang, B. -W., Jin, C. -C., Jin, G., Kuulkers, E., Li, C. -K., Li, D. -Y., Li, J. -F., Li, L. -H., Li, M. -S., Li, W., Li, Z. -D., Liu, C. -Z, Liu, H. -Y., Liu, H. -Q., Liu, M. -J., Lu, F. -J., Luo, L. -D., Ma, J., Mao, X., Nandra, K., O'Brien, P., Pan, H. -W., Rau, A., Rea, N., Sanders, J., Song, L. -M., Sun, S. -L., Sun, X. -J., Tan, Y. -Y., Tang, Q. -J., Tao, Y. -H., Wang, H., Wang, J., Wang, L., Wang, W. -X., Wang, Y. -L., Wang, Y. -S., Xiong, D. -R., Xu, H. -T., Xu, J. -J., Xu, X. -P., Xu, Y. -F., Xu, Z., Xue, C. -B., Xue, Y. -L., Yan, A. -L., Yang, H. -N., Yang, X. -T., Yang, Y. -J., Zhang, C., Zhang, J., Zhang, M., Zhang, S. -N., Zhang, W. -D., Zhang, W. -J., Zhang, Y. -H., Zhang, Z., Zhang, Z. -L., Zhao, D. -H., Zhao, H. -S., Zhao, X. -F., Zhao, Z. -J., Zhou, Y. -L., Zhu, Y. -X., and Zhu, Z. -C.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Massive stars end their life as core-collapse supernovae, amongst which some extremes are Type Ic broad-lined supernovae associated with long-duration gamma-ray bursts (LGRBs) having powerful relativistic jets. Their less-extreme brethren make unsuccessful jets that are choked inside the stars, appearing as X-ray flashes or low-luminosity GRBs. On the other hand, there exists a population of extragalactic fast X-ray transients (EFXTs) with timescales ranging from seconds to thousands of seconds, whose origins remain obscure. Known sources that contribute to the observed EFXT population include the softer analogs of LGRBs, shock breakouts of supernovae, or unsuccessful jets. Here, we report the discovery of the bright X-ray transient EP240414a detected by the Einstein Probe (EP), which is associated with the Type Ic supernova SN 2024gsa at a redshift of 0.401. The X-ray emission evolution is characterised by a very soft energy spectrum peaking at < 1.3 keV, which makes it distinct from known LGRBs, X-ray flashes, or low-luminosity GRBs. Follow-up observations at optical and radio bands revealed the existence of a weak relativistic jet that interacts with an extended shell surrounding the progenitor star. Located on the outskirts of a massive galaxy, this event reveals a new population of explosions of Wolf-Rayet stars characterised by a less powerful engine that drives a successful but weak jet, possibly owing to a progenitor star with a smaller core angular momentum than in traditional LGRB progenitors., Comment: 43 pages, 9 figures, 4 tables, submitted. Comments are welcome
Published: 2024

2. Hadronic cross section measurements with the DAMPE space mission using 20GeV-10TeV cosmic-ray protons and $^4$He

Author: Alemanno, F., An, Q., Azzarello, P., Barbato, F. C. T., Bernardini, P., Bi, X. J., Cagnoli, I., Cai, M. S., Casilli, E., Catanzani, E., Chang, J., Chen, D. Y., Chen, J. L., Chen, Z. F., Coppin, P., Cui, M. Y., Cui, T. S., Cui, Y. X., Dai, H. T., De Benedittis, A., De Mitri, I., de Palma, F., Di Giovanni, A., Ding, Q., Dong, T. K., Dong, Z. X., Donvito, G., Droz, D., Duan, J. L., Duan, K. K., Fan, R. R., Fan, Y. Z., Fang, F., Fang, K., Feng, C. Q., Feng, L., Frieden, J. M., Fusco, P., Gao, M., Gargano, F., Gong, K., Gong, Y. Z., Guo, D. Y., Guo, J. H., Han, S. X., Hu, Y. M., Huang, G. S., Huang, X. Y., Huang, Y. Y., Ionica, M., Jiang, L. Y., Jiang, Y. Z., Jiang, W., Kong, J., Kotenko, A., Kyratzis, D., Lei, S. J., Li, W. H., Li, W. L., Li, X., Li, X. Q., Liang, Y. M., Liu, C. M., Liu, H., Liu, J., Liu, S. B., 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., Putti-Garcia, E., Qiao, R., Rao, J. N., Ruina, A., Sarkar, R., Savina, P., Serpolla, A., Shangguan, Z., Shen, W. H., Shen, Z. Q., Shen, Z. T., Silveri, L., Song, J. X., Stolpovskiy, M., Su, H., Su, M., Sun, H. R., Sun, Z. Y., Surdo, A., Teng, X. J., Tykhonov, A., Wang, J. Z., Wang, L. G., Wang, S., Wang, S. X., Wang, X. L., Wang, Y., Wang, Y. F., Wang, Y. Z., Wang, Z. M., Wei, D. M., Wei, J. J., Wei, Y. F., Wu, D., Wu, J., Wu, S. S., Wu, X., Xia, Z. Q., Xu, H. T., Xu, J., Xu, Z. H., Xu, Z. L., Xu, E. H., 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, S. X., Zhang, W. Z., Zhang, Yan, Zhang, Yi, 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: High Energy Physics - Experiment
Abstract: Precise direct cosmic-ray (CR) measurements provide an important probe to study the energetic particle sources in our Galaxy, and the interstellar environment through which these particles propagate. Uncertainties on hadronic models, ion-nucleon cross sections in particular, are currently the limiting factor towards obtaining more accurate CR ion flux measurements with calorimetric space-based experiments. We present an energy-dependent measurement of the inelastic cross section of protons and helium-4 nuclei (alpha particles) on a Bi$_4$Ge$_3$O$_{12}$ target, using 88 months of data collected by the DAMPE space mission. The kinetic energy range per nucleon of the measurement points ranges from 18 GeV to 9 TeV for protons, and from 5 GeV/n to 3 TeV/n for helium-4 nuclei. Our results lead to a significant improvement of the CR flux normalisation. In the case of helium-4, these results correspond to the first cross section measurements on a heavy target material at energies above 10 GeV/n., Comment: 17 pages, submitted to PRD
Published: 2024

3. Soft X-ray prompt emission from a high-redshift gamma-ray burst EP240315a

Author: Liu, Y., Sun, H., Xu, D., Svinkin, D. S., Delaunay, J., Tanvir, N. R., Gao, H., Zhang, C., Chen, Y., Wu, X. -F., Zhang, B., Yuan, W., An, J., Bruni, G., Frederiks, D. D., Ghirlanda, G., Hu, J. -W., Li, A., Li, C. -K., Li, J. -D., Malesani, D. B., Piro, L., Raman, G., Ricci, R., Troja, E., Vergani, S. D., Wu, Q. -Y., Yang, J., Zhang, B. -B., Zhu, Z. -P., Postigo, A. de Ugarte, Demin, A. G., Dobie, D., Fan, Z., Fu, S. -Y., Fynbo, J. P. U., Geng, J. -J., Gianfagna, G., Hu, Y. -D., Huang, Y. -F., Jiang, S. -Q., Jonker, P. G., Julakanti, Y., Kennea, J. A., Kokomov, A. A., Kuulkers, E., Lei, W. -H., Leung, J. K., Levan, A. J., Li, D. -Y., Li, Y., Littlefair, S. P., Liu, X., Lysenko, A. L., Ma, Y. -N., Martin-Carrillo, A., O'Brien, P., Parsotan, T., Quirola-Vasquez, J., Ridnaia, A. V., Ronchini, S., Rossi, A., Mata-Sanchez, D., Schneider, B., Shen, R. -F., Thakur, A. L., Tohuvavohu, A., Torres, M. A. P., Tsvetkova, A. E., Ulanov, M. V., Wei, J. -J., Xiao, D., Yin, Y. -H. I., Bai, M., Burwitz, V., Cai, Z. -M., Chen, F. -S., Chen, H. -L., Chen, T. -X., Chen, W., Chen, Y. -F., Chen, Y. -H., Cheng, H. -Q., Cui, C. -Z., Cui, W. -W., Dai, Y. -F., Dai, Z. -G., Eder, J., Fan, D. -W., Feldman, C., Feng, H., Feng, Z., Friedrich, P., Gao, X., Guan, J., Han, D. -W, Han, J., Hou, D. -J., Hu, H. -B., Hu, T., Huang, M. -H., Huo, J., Hutchinson, I., Ji, Z., Jia, S. -M., Jia, Z. -Q., Jiang, B. -W., Jin, C. -C., Jin, G., Jin, J. -J., Keereman, A., Lerman, H., Li, J. -F., Li, L. -H., Li, M. -S., Li, W., Li, Z. -D., Lian, T. -Y., Liang, E. -W., Ling, Z. -X., Liu, C. -Z., Liu, H. -Y., Liu, H. -Q., Liu, M. -J., Liu, Y. -R., Lu, F. -J., LU, H. -J., Luo, L. -D., Ma, F. L., Ma, J., Mao, J. -R., Mao, X., McHugh, M., Meidinger, N., Nandra, K., Osborne, J. P., Pan, H. -W., Pan, X., Ravasio, M. E., Rau, A., Rea, N., Rehman, U., Sanders, J., Santovincenzo, A., Song, L. -M., Su, J., Sun, L. -J., Sun, S. -L., Sun, X. -J., Tan, Y. -Y., Tang, Q. -J., Tao, Y. -H., Tong, J. -Z., Wang, H., Wang, J., Wang, L., Wang, W. -X., Wang, X. -F., Wang, X. -Y., Wang, Y. -L., Wang, Y. -S., Wei, D. -M., Willingale, R., Xiong, S. -L., Xu, H. -T., Xu, J. -J., Xu, X. -P., Xu, Y. -F., Xu, Z., Xue, C. -B., Xue, Y. -L., Yan, A. -L., Yang, F., Yang, H. -N., Yang, X. -T., Yang, Y. -J, Yu, Y. -W., Zhang, J., Zhang, M., Zhang, S. -N., Zhang, W. -D., Zhang, W. -J., Zhang, Y. -H., Zhang, Z., Zhang, Z. -L., Zhao, D. -H., Zhao, H. -S., Zhao, X. -F., Zhao, Z. -J., Zhou, L. -X., Zhou, Y. -L., Zhu, Y. -X., Zhu, Z. -C., and Zuo, X. -X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Long gamma-ray bursts (GRBs) are believed to originate from core collapse of massive stars. High-redshift GRBs can probe the star formation and reionization history of the early universe, but their detection remains rare. Here we report the detection of a GRB triggered in the 0.5--4 keV band by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated as EP240315a, whose bright peak was also detected by the Swift Burst Alert Telescope and Konus-Wind through off-line analyses. At a redshift of $z=4.859$, EP240315a showed a much longer and more complicated light curve in the soft X-ray band than in gamma-rays. Benefiting from a large field-of-view ($\sim$3600 deg$^2$) and a high sensitivity, EP-WXT captured the earlier engine activation and extended late engine activity through a continuous detection. With a peak X-ray flux at the faint end of previously known high-$z$ GRBs, the detection of EP240315a demonstrates the great potential for EP to study the early universe via GRBs., Comment: 41 pages, 8 figures, 7 tables
Published: 2024

4. Measurement of the cosmic p+He energy spectrum from 50 GeV to 0.5 PeV with the DAMPE space mission

Author: DAMPE Collaboration, Alemanno, F., Altomare, C., An, Q., Azzarello, P., Barbato, F. C. T., Bernardini, P., Bi, X. J., Cagnoli, I., Cai, M. S., Casilli, E., Catanzani, E., Chang, J., Chen, D. Y., Chen, J. L., Chen, Z. F., Coppin, P., Cui, M. Y., Cui, T. S., Cui, Y. X., Dai, H. T., De Benedittis, A., De Mitri, I., de Palma, F., Deliyergiyev, M., Di Giovanni, A., Di Santo, M., Ding, Q., Dong, T. K., Dong, Z. X., Donvito, G., Droz, D., Duan, J. L., Duan, K. K., Fan, R. R., Fan, Y. Z., Fang, F., Fang, K., Feng, C. Q., Feng, L., Alonso, M. Fernandez, Frieden, J. M., Fusco, P., Gao, M., Gargano, F., Gong, K., Gong, Y. Z., Guo, D. Y., Guo, J. H., Han, S. X., Hu, Y. M., Huang, G. S., Huang, X. Y., Huang, Y. Y., Ionica, M., Jiang, L. Y., Jiang, Y. Z., Jiang, W., Kong, J., Kotenko, A., Kyratzis, D., Lei, S. J., Li, W. H., Li, W. L., Li, X., Li, X. Q., Liang, Y. M., Liu, C. M., Liu, H., Liu, J., Liu, S. B., Liu, Y., Loparco, F., Luo, C. N., Ma, M., Ma, P. X., Ma, T., Ma, X. Y., Marsella, G., Mazziotta, M. N., Mo, D., Salinas, M. Muñoz, Niu, X. Y., Pan, X., Parenti, A., Peng, W. X., Peng, X. Y., Perrina, C., Putti-Garcia, E., Qiao, R., Rao, J. N., Ruina, A., Shangguan, Z., Shen, W. H., Shen, Z. Q., Shen, Z. T., Silveri, L., Song, J. X., Stolpovskiy, M., Su, H., Su, M., Sun, H. R., Sun, Z. Y., Surdo, A., Teng, X. J., Tykhonov, A., Wang, J. Z., Wang, L. G., Wang, S., Wang, S. X., Wang, X. L., Wang, Y., Wang, Y. F., Wang, Y. Z., Wang, Z. M., Wei, D. M., Wei, J. J., Wei, Y. F., Wu, D., Wu, J., Wu, L. B., Wu, S. S., Wu, X., Xia, Z. Q., Xu, H. T., Xu, J., Xu, Z. H., Xu, Z. L., Xu, E. H., 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, S. X., Zhang, W. Z., Zhang, Yan, Zhang, Yi, 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, High Energy Physics - Experiment
Abstract: Recent observations of the light component of the cosmic-ray spectrum have revealed unexpected features that motivate further and more precise measurements up to the highest energies. The Dark Matter Particle Explorer is a satellite-based cosmic-ray experiment that has been operational since December 2015, continuously collecting data on high-energy cosmic particles with very good statistics, energy resolution, and particle identification capabilities. In this work, the latest measurements of the energy spectrum of proton+helium in the energy range from 46 GeV to 464 TeV are presented. Among the most distinctive features of the spectrum, a spectral hardening at 600 GeV has been observed, along with a softening at 29 TeV measured with a 6.6{\sigma} significance. Moreover, the detector features and the analysis approach allowed for the extension of the spectral measurement up to the sub-PeV region. Even if with small statistical significance due to the low number of events, data suggest a new spectral hardening at about 150 TeV., Comment: Published on PRD
Published: 2023
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5. GRANDMA and HXMT Observations of GRB 221009A -- the Standard-Luminosity Afterglow of a Hyper-Luminous Gamma-Ray Burst

Author: Kann, D. A., Agayeva, S., Aivazyan, V., Alishov, S., Andrade, C. M., Antier, S., Baransky, A., Bendjoya, P., Benkhaldoun, Z., Beradze, S., Berezin, D., Boër, M., Broens, E., Brunier, S., Bulla, M., Burkhonov, O., Burns, E., Chen, Y., Chen, Y. P., Conti, M., Coughlin, M. W., Cui, W. W., Daigne, F., Delaveau, B., Devillepoix, H. A. R., Dietrich, T., Dornic, D., Dubois, F., Ducoin, J. -G., Durand, E., Duverne, P. -A., Eggenstein, H. -B., Ehgamberdiev, S., Fouad, A., Freeberg, M., Froebrich, D., Ge, M. Y., Gervasoni, S., Godunova, V., Gokuldass, P., Gurbanov, E., Han, D. W., Hasanov, E., Hello, P., Hussenot-Desenonges, T., Inasaridze, R., Iskandar, A., Ismailov, N., Janati, A., Laz, T. Jegou du, Jia, S. M., Karpov, S., Kaeouach, A., Kiendrebeogo, R. W., Klotz, A., Kneip, R., Kochiashvili, N., Kunert, N., Lekic, A., Leonini, S., Li, C. K., Li, W., Li, X. B., Liao, J. Y., Logie, L., Lu, F. J., Mao, J., Marchais, D., Ménard, R., Morris, D., Natsvlishvili, R., Nedora, V., Noonan, K., Noysena, K., Orange, N. B., Pang, P. T. H., Peng, H. W., Pellouin, C., Peloton, J., Pradier, T., Pyshna, O., Rajabo, Y., Rau, S., Rinner, C., Rivet, J. -P., Romanov, F. D., Rosi, P., Rupchandani, V. A., Serrau, M., Shokry, A., Simon, A., Smith, K., Sokoliuk, O., Soliman, M., Song, L. M., Takey, A., Tillayev, Y., Ramirez, L. M. Tinjaca, Melo, I. Tosta e, Turpin, D., Postigo, A. de Ugarte, Vanaverbeke, S., Vasylenko, V., Vernet, D., Vidadi, Z., Wang, C., Wang, J., Wang, L. T., Wang, X. F., Xiong, Shaolin L., Xu, Y. P., Xue, W. C., Zeng, X., Zhang, S. N., Zhao, H. S., and Zhao, X. F.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: GRB 221009A is the brightest Gamma-Ray Burst (GRB) detected in more than 50 years of study. In this paper, we present observations in the X-ray and optical domains after the GRB obtained by the GRANDMA Collaboration (which includes observations from more than 30 professional and amateur telescopes) and the Insight-HXMT Collaboration. We study the optical afterglow with empirical fitting from GRANDMA+HXMT data, augmented with data from the literature up to 60 days. We then model numerically, using a Bayesian approach, the GRANDMA and HXMT-LE afterglow observations, that we augment with Swift-XRT and additional optical/NIR observations reported in the literature. We find that the GRB afterglow, extinguished by a large dust column, is most likely behind a combination of a large Milky-Way dust column combined with moderate low-metallicity dust in the host galaxy. Using the GRANDMA+HXMT-LE+XRT dataset, we find that the simplest model, where the observed afterglow is produced by synchrotron radiation at the forward external shock during the deceleration of a top-hat relativistic jet by a uniform medium, fits the multi-wavelength observations only moderately well, with a tension between the observed temporal and spectral evolution. This tension is confirmed when using the extended dataset. We find that the consideration of a jet structure (Gaussian or power-law), the inclusion of synchrotron self-Compton emission, or the presence of an underlying supernova do not improve the predictions, showing that the modelling of GRB22109A will require going beyond the most standard GRB afterglow model. Placed in the global context of GRB optical afterglows, we find the afterglow of GRB 221009A is luminous but not extraordinarily so, highlighting that some aspects of this GRB do not deviate from the global known sample despite its extreme energetics and the peculiar afterglow evolution., Comment: Accepted to ApJL for the special issue, 37 pages, 23 pages main text, 6 tables, 13 figures
Published: 2023
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6. Search for relativistic fractionally charged particles in space

Author: DAMPE Collaboration, Alemanno, F., Altomare, C., An, Q., Azzarello, P., Barbato, F. C. T., Bernardini, P., Bi, X. J., Cai, M. S., Casilli, E., 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., De-Benedittis, A., De Mitri, I., de Palma, F., Deliyergiyev, M., Di Giovanni, A., Di Santo, M., Ding, Q., 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, F., Fang, K., Feng, C. Q., Feng, L., Alonso, M. F., Frieden, J. M., Fusco, P., Gao, M., Gargano, F., Gong, K., Gong, Y. Z., Guo, D. Y., Guo, J. H., Han, S. X., Hu, Y. M., Huang, G. S., Huang, X. Y., Huang, Y. Y., Ionica, M., Jiang, L. Y., Jiang, W., Kong, J., Kotenko, A., Kyratzis, D., Lei, S. J., Li, W. L., Li, W. H., Li, X., Li, X. Q., Liang, Y. M., Liu, C. M., Liu, H., Liu, J., Liu, S. B., Liu, Y., Loparco, F., Luo, C. N., Ma, M., Ma, P. X., Ma, T., Ma, X. Y., Marsella, G., Mazziotta, M. N., Mo, D., Salinas, M. M., Niu, X. Y., Pan, X., Parenti, A., Peng, W. X., Peng, X. Y., Perrina, C., Qiao, R., Rao, J. N., Ruina, A., Shangguan, Z., Shen, W. H., Shen, Z. Q., Shen, Z. T., Silveri, L., Song, J. X., Stolpovskiy, M., Su, H., Su, M., Sun, H. R., Sun, Z. Y., Surdo, A., Teng, X. J., Tykhonov, A., Wang, J. Z., Wang, L. G., Wang, S., Wang, S. X., Wang, X. L., Wang, Y., Wang, Y. F., Wang, Y. Z., Wei, D. M., Wei, J. J., Wei, Y. F., Wu, D., Wu, J., Wu, L. B., Wu, S. S., Wu, X., Xia, Z. Q., Xu, E. H., Xu, H. T., Xu, J., 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, S. X., Zhang, W. Z., Zhang, Yan, Zhang, Yi., 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, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Physics - Space Physics
Abstract: More than a century after the performance of the oil drop experiment, the possible existence of fractionally charged particles FCP still remains unsettled. The search for FCPs is crucial for some extensions of the Standard Model in particle physics. Most of the previously conducted searches for FCPs in cosmic rays were based on experiments underground or at high altitudes. However, there have been few searches for FCPs in cosmic rays carried out in orbit other than AMS-01 flown by a space shuttle and BESS by a balloon at the top of the atmosphere. In this study, we conduct an FCP search in space based on on-orbit data obtained using the DArk Matter Particle Explorer (DAMPE) satellite over a period of five years. Unlike underground experiments, which require an FCP energy of the order of hundreds of GeV, our FCP search starts at only a few GeV. An upper limit of $6.2\times 10^{-10}~~\mathrm{cm^{-2}sr^{-1} s^{-1}}$ is obtained for the flux. Our results demonstrate that DAMPE exhibits higher sensitivity than experiments of similar types by three orders of magnitude that more stringently restricts the conditions for the existence of FCP in primary cosmic rays., Comment: 19 pages, 6 figures, accepted by PRD
Published: 2022
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7. Peculiar disk behaviors of the black hole candidate MAXI J1348-630 in the hard state observed by Insight-HXMT and Swift

Author: Zhang, W., Tao, L., Soria, R., Qu, J. L., Zhang, S. N., Weng, S. S., zhang, L., Wang, Y. N., Huang, Y., Ma, R. C., Zhang, S., Ge, M. Y., Song, L. M., Ma, X., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, C. Z., Liu, H. X., Liu, H. W., Liu, X. J., Lu, F. J., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, R. J., Yang, S., Yang, Y. J., Yang, Y. R., Yi, Q. B., Yin, Q. Q., Yuan, Y., Zhang, F., Zhang, H. M., Zhang, P., Zhang, W. C., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present a spectral study of the black hole candidate MAXI J1348-630 during its 2019 outburst, based on monitoring observations with Insight-HXMT and Swift. Throughout the outburst, the spectra are well fitted with power-law plus disk-blackbody components. In the soft-intermediate and soft states, we observed the canonical relation L ~ T_in^4 between disk luminosity L and peak colour temperature T_in, with a constant inner radius R_in (traditionally identified with the innermost stable circular orbit). At other stages of the outburst cycle, the behaviour is more unusual, inconsistent with the canonical outburst evolution of black hole transients. In particular, during the hard rise, the apparent inner radius is smaller than in the soft state (and increasing), and the peak colour temperature is higher (and decreasing). This anomalous behaviour is found even when we model the spectra with self-consistent Comptonization models, which take into account the up-scattering of photons from the disk component into the power-law component. To explain both those anomalous trends at the same time, we suggest that the hardening factor for the inner disk emission was larger than the canonical value of ~1.7 at the beginning of the outburst. A more physical trend of radii and temperature evolution requires a hardening factor evolving from ~3.5 at the beginning of the hard state to ~1.7 in the hard intermediate state. This could be evidence that the inner disk was in the process of condensing from the hot, optically thin medium and had not yet reached a sufficiently high optical depth for its emission spectrum to be described by the standard optically-thick disk solution., Comment: 20 pages, 10 figures, 4 tables, accepted by ApJ
Published: 2022
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8. Search for Gamma-Ray Bursts and Gravitational Wave Electromagnetic Counterparts with High Energy X-ray Telescope of \textit{Insight}-HXMT

Author: Cai, C., Xiong, S. L., Li, C. K., Liu, C. Z., Zhang, S. N., Li, X. B., Song, L. M., Li, B., Xiao, S., Yi, Q. B., Zhu, Y., Zheng, Y. G., Chen, W., Luo, Q., Huang, Y., Song, X. Y., Zhao, H. S., Zhao, Y., Zhang, Z., Bu, Q. C., Cao, X. L., Chang, Z., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, G., Li, T. P., Li, W., Li, X., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, H. W., Liu, H. X., Liu, X. J., Lu, F. J., Lu, X. F., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Qu, J. L., Ren, X. Q., Sai, N., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xu, Y. P., Yang, R. J., Yang, S., Yang, Y. J., Yang, Y. R., Yang, X. J., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, S., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhang, Y. H., Zhao, X. F., Zheng, S. J., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The High Energy X-ray telescope (HE) on-board the Hard X-ray Modulation Telescope (\textit{Insight}-HXMT) can serve as a wide Field of View (FOV) gamma-ray monitor with high time resolution ($\mu$s) and large effective area (up to thousands cm$^2$). We developed a pipeline to search for Gamma-Ray Bursts (GRBs), using the traditional signal-to-noise ratio (SNR) method for blind search and the coherent search method for targeted search. By taking into account the location and spectrum of the burst and the detector response, the targeted coherent search is more powerful to unveil weak and sub-threshold bursts, especially those in temporal coincidence with Gravitational Wave (GW) events. Based on the original method in literature, we further improved the coherent search to filter out false triggers caused by spikes in light curves, which are commonly seen in gamma-ray instruments (e.g. \textit{Fermi}/GBM, \textit{POLAR}). We show that our improved targeted coherent search method could eliminate almost all false triggers caused by spikes. Based on the first two years of \textit{Insight}-HXMT/HE data, our targeted search recovered 40 GRBs, which were detected by either \textit{Swift}/BAT or \textit{Fermi}/GBM but too weak to be found in our blind search. With this coherent search pipeline, the GRB detection sensitivity of \textit{Insight}-HXMT/HE is increased to about 1.5E-08 erg/cm$^2$ (200 keV$-$3 MeV). We also used this targeted coherent method to search \textit{Insight}-HXMT/HE data for electromagnetic (EM) counterparts of LIGO-Virgo GW events (including O2 and O3a runs). However, we did not find any significant burst associated with GW events., Comment: 12 pages, 14 figures, 5 tables; accepted for publication in MNRAS
Published: 2021
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9. Measurement of the cosmic ray helium energy spectrum from 70 GeV to 80 TeV with the DAMPE space mission

Author: 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, High Energy Physics - Experiment
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
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10. Accretion Torque Reversals in GRO J1008-57 Revealed by Insight-HXMT

Author: Wang, W., Tang, Y. M., Tuo, Y. L., Epili, P. R., Zhang, S. N., Song, L. M., Lu, F. J., Qu, J. L., Zhang, S., Ge, M. Y., Huang, Y., Li, B., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, C. K., Li, G., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, C. Z., Liu, H. X., Liu, H. W., Lu, X. F., Luo, Q., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tao, L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, Y. P., Yang, R. J., Yang, S., Yang, J. J., Yang, Y. J., Yi, B. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W., Zhang, W. C., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: GRO J1008-57, as a Be/X-ray transient pulsar, is considered to have the highest magnetic field in known neutron star X-ray binary systems. Observational data of the X-ray outbursts in GRO J1008-57 from 2017 to 2020 were collected by the Insight-HXMT satellite. In this work, the spin period of the neutron star in GRO J1008-57 was determined to be about 93.28 seconds in August 2017, 93.22 seconds in February 2018, 93.25 seconds in June 2019 and 93.14 seconds in June 2020. GRO J1008-57 evolved in the spin-up process with a mean rate of $-(2.10\pm 0.05)\times$10$^{-4}$ s/d from 2009 -- 2018, and turned into a spin down process with a rate of $(6.7\pm 0.6)\times$10$^{-5}$ s/d from Feb 2018 to June 2019. During the type II outburst of 2020, GRO J1008-57 had the spin-up torque again. During the torque reversals, the pulse profiles and continuum X-ray spectra did not change significantly, and the cyclotron resonant scattering feature around 80 keV was only detected during the outbursts in 2017 and 2020. Based on the observed mean spin-up rate, we estimated the inner accretion disk radius in GRO J1008-57 (about 1 - 2 times of the Alfv\'{e}n radius) by comparing different accretion torque models of magnetic neutron stars. During the spin-down process, the magnetic torque should dominate over the matter accreting inflow torque, and we constrained the surface dipole magnetic field $B\geq 6\times 10^{12}$ G for the neutron star in GRO J1008-57, which is consistent with the magnetic field strength obtained by cyclotron line centroid energy., Comment: 10 pages, 5 figures, and 3 tables, the Journal of High Energy Astrophysics in press
Published: 2021

11. QPOs and Orbital elements of X-ray binary 4U 0115+63 during the 2017 outburst observed by Insight-HXMT

Author: Ding, Y. Z., Wang, W., Zhang, P., Bu, Q. C., Cai, C., Cao, X. L., Zhi, C., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, C. Z., Liu, H. X., Liu, H. W., Liu, X. J., Lu, F. J., Lu, X. F., L., Q., T., L., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Qu, J. L., Ren, X. Q., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, Y. P., Yang, R. J., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, S., Zhang, S. N., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: In this paper, we presented a detailed timing analysis of a prominent outburst of 4U 0115+63 detected by \textit{Insight}-HXMT in 2017 August. The spin period of the neutron star was determined to be $3.61398\pm 0.00002$ s at MJD 57978. We measured the period variability and extract the orbital elements of the binary system. The angle of periastron evolved with a rate of $0.048\pm0.003$ $yr^{-1}$. The light curves are folded to sketch the pulse profiles in different energy ranges. A multi-peak structure in 1-10 keV is clearly illustrated. We introduced wavelet analysis into our data analysis procedures to study QPO signals and perform a detailed wavelet analysis in many different energy ranges. Through the wavelet spectra, we report the discovery of a QPO at the frequency $\sim 10$ mHz. In addition, the X-ray light curves showed multiple QPOs in the period of $\sim 16-32 $ s and $\sim 67- 200 $ s. We found that the $\sim100$ s QPO was significant in most of the observations and energies. There exist positive relations between X-ray luminosity and their Q-factors and S-factors, while the QPO periods have no correlation with X-ray luminosity. In wavelet phase maps, we found that the pulse phase of $\sim 67- 200 $ s QPO drifting frequently while the $\sim 16-32 $ s QPO scarcely drifting. The dissipation of oscillations from high energy to low energy was also observed. These features of QPOs in 4U 0115+63 provide new challenge to our understanding of their physical origins., Comment: 14 pages, 9 figures, and 6 tables. This work has been submitted to MNRAS after the referee's report
Published: 2021
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12. Insight-HXMT observations of Swift J0243.6+6124: the evolution of RMS pulse fractions at super-Eddington luminosity

Author: Wang, P. J., Kong, L. D., Zhang, S., Chen, Y. P., Zhang, S. N., Qu, J. L., Ji, L., Tao, L., Ge, M. Y., Lu, F. J., Chen, L., Song, L. M., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Bu, Q. C., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, L. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Yan Ji, Yang, Yi Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Zhao, Zhang, Zhi, Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., Zhou, D. K., Zhou, J. F., Zhu, Y. X., Zhu, Y., and Zhuang, R. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Based on Insight-HXMT data, we report on the pulse fraction evolution during the 2017-2018 outburst of the newly discovered first Galactic ultraluminous X-ray source (ULX) Swift J0243.6+6124. The pulse fractions of 19 observation pairs selected in the rising and fading phases with similar luminosity are investigated. The results show a general trend of the pulse fraction increasing with luminosity and energy at super-critical luminosity. However, the relative strength of the pulsation between each pair evolves strongly with luminosity. The pulse fraction in the rising phase is larger at luminosity below $7.71\times10^{38}$~erg~s$^{-1}$, but smaller at above. A transition luminosity is found to be energy independent. Such a phenomena is firstly confirmed by Insight-HXMT observations and we speculate it may have relation with the radiation pressure dominated accretion disk.
Published: 2020
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13. Physical origin of the nonphysical spin evolution of MAXI J1820+070

Author: Guan, J., Tao, L., Qu, J. L., Zhang, S. N., Zhang, W., Zhang, S., Ma, R. C., Ge, M. Y., Song, L. M., Lu, F. J., Li, T. P., Xu, Y. P., Chen, Y., Cao, X. L., Liu, C. Z., Zhang, L., Wang, Y. N., Chen, Y. P., Bu, Q. C., Cai, C., Chang, Z., Chen, L., Chen, T. X., Chen, Y. B., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gu, Y. D., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, H. W., Liu, H. X., Liu, X. J., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, R. J., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W. C., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, 83C57
Abstract: We report on the Insight-HXMT observations of the new black hole X-ray binary MAXI J1820+070 during its 2018 outburst. Detailed spectral analysis via the continuum fitting method shows an evolution of the inferred spin during its high soft sate. Moreover, the hardness ratio, the non-thermal luminosity and the reflection fraction also undergo an evolution, exactly coincident to the period when the inferred spin transition takes place. The unphysical evolution of the spin is attributed to the evolution of the inner disc, which is caused by the collapse of a hot corona due to condensation mechanism or may be related to the deceleration of a jet-like corona. The studies of the inner disc radius and the relation between the disc luminosity and the inner disc radius suggest that, only at a particular epoch, did the inner edge of the disc reach the innermost stable circular orbit and the spin measurement is reliable. We then constrain the spin of MAXI J1820+070 to be a*=0.2^{+0.2}_{-0.3}. Such a slowly spinning black hole possessing a strong jet suggests that its jet activity is driven mainly by the accretion disc rather than by the black hole spin., Comment: 14 pages, 13 figures, 5 tables, accepted for publication in MNRAS
Published: 2020
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14. X-ray reprocessing in accreting pulsar GX 301-2 observed with Insight-HXMT

Author: Ji, L., Doroshenko, V., Suleimanov, V., Santangelo, A., Orlandini, M., Liu, J., Ducci, L., Zhang, S. N., Nabizadeh, A., Gavran, D., Zhang, S., Ge, M. Y., Li, X. B., Tao, L., Bu, Q. C., Qu, J. L., Lu, F. J., Chen, L., Song, L. M., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, T. X., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, W., Li, X., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, H. X., Liu, H. W., Liu, X. J., Lu, X. F., Luo, Q., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, R. J., Yang, S., Yang, Yan-Ji, Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W., Zhang, W. C., Zhang, Yi, Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We investigate the absorption and emission features in observations of GX 301-2 detected with Insight-HXMT/LE in 2017-2019. At different orbital phases, we found prominent Fe Kalpha, Kbeta and Ni Kalpha lines, as well as Compton shoulders and Fe K-shell absorption edges. These features are due to the X-ray reprocessing caused by the interaction between the radiation from the source and surrounding accretion material. According to the ratio of iron lines Kalpha and Kbeta, we infer the accretion material is in a low ionisation state. We find an orbital-dependent local absorption column density, which has a large value and strong variability around the periastron. We explain its variability as a result of inhomogeneities of the accretion environment and/or instabilities of accretion processes. In addition, the variable local column density is correlated with the equivalent width of the iron Kalpha lines throughout the orbit, which suggests that the accretion material near the neutron star is spherically distributed., Comment: 10 pages, 5 figures, 2 tables, accepted for publication in MNRAS
Published: 2020
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15. Insight-HXMT observations of a possible fast transition from jet to wind dominated state during a huge flare of GRS~1915+105

Author: Kong, L. D., Zhang, S., Chen, Y. P., Zhang, S. N., Ji, L., Wang, P. J., Tao, L., Ge, M. Y., Liu, C. Z., Song, L. M., Lu, F. J., Qu, J. L., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Bu, Q. C., Cai, C., Chang, Z., Chen, G., Chen, L., Chen, T. X., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Li, B., Li, C. K., Li, G., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, H. W., Liu, H. X., Liu, X. J., Lu, X. F., Luo, Q., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, L. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, R. J., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the analysis of the brightest flare that was recorded in the \emph{Insight}-HMXT data set, in a broad energy range (2$-$200 keV) from the microquasar GRS~1915+105 during an unusual low-luminosity state. This flare was detected by \emph{Insight}-HXMT among a series of flares during 2 June 2019 UTC 16:37:06 to 20:11:36, with a 2-200 keV luminosity of 3.4$-$7.27$\times10^{38}$ erg s$^{-1}$. Basing on the broad-band spectral analysis, we find that the flare spectrum shows different behaviors during bright and faint epochs. The spectrum of the flare can be fitted with a model dominated by a power-law component. Additional components show up in the bright epoch with a hard tail and in the faint epoch with an absorption line $\sim$ 6.78 keV. The reflection component of the latter is consistent with an inner disk radius $\sim$ 5 times larger than that of the former. These results on the giant flare during the "unusual" low-luminosity state of GRS~1915+105 may suggest that the source experiences a possible fast transition from a jet-dominated state to a wind-dominated state. We speculate that the evolving accretion disk and the large-scale magnetic field may play important roles in this peculiar huge flare.
Published: 2020
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16. A variable ionized disk wind in the black-hole candidate EXO 1846-031

Author: Wang, Yanan, Ji, Long, Garcia, Javier A., Dauser, Thomas, Mendez, Mariano, Mao, Junjie, Tao, L., Altamirano, Diego, Maggi, Pierre, Zhang, S. N., Ge, M. Y., Zhang, L., Qu, J. L., Zhang, S., Ma, X., Lu, F. J., Li, T. P., Huang, Y., Zheng, S. J., Chang, Z., Tuo, Y. L., Song, L. M., Xu, Y. P., Chen, Y., Liu, C. Z., Bu, Q. C., Cai, C., Cao, X. L., Chen, L., Chen, T. X., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, H. W., Liu, X. J., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Wang, W. S., Wang, Y. D., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhao, H. S., Zhao, X. F., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: After 34 years, the black-hole candidate EXO 1846-031 went into outburst again in 2019. We investigate its spectral properties in the hard intermediate and the soft states with NuSTAR and Insight-HXMT. A reflection component has been detected in the two spectral states but possibly originating from different illumination spectra: in the intermediate state, the illuminating source is attributed to a hard coronal component, which has been commonly observed in other X-ray binaries, whereas in the soft state the reflection is probably produced by the disk self-irradiation. Both cases support EXO 1846-031 as a low inclination system of ~40 degrees. An absorption line is clearly detected at ~7.2 keV in the hard intermediate state, corresponding to a highly ionized disk wind (log {\xi} > 6.1) with a velocity up to 0.06c. Meanwhile, quasi-simultaneous radio emissions have been detected before and after the X-rays, implying the co-existence of disk winds and jets in this system. Additionally, the observed wind in this source is potentially driven by magnetic forces. The absorption line disappeared in the soft state and a narrow emission line appeared at ~6.7 keV on top of the reflection component, which may be evidence for disk winds, but data with the higher spectral resolution are required to examine this., Comment: Accepted for publication in ApJ
Published: 2020
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17. Constraining the transient high-energy activity of FRB180916.J0158+65 with Insight-HXMT followup observations

Author: Guidorzi, C., Orlandini, M., Frontera, F., Nicastro, L., Xiong, S. L., Liao, J. Y., Li, G., Zhang, S. N., Amati, L., Virgilli, E., Zhang, S., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, L., Chen, T. X., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liu, B. S., Liu, C. Z., Liu, H. X., Liu, H. W., Liu, X. J., Lu, F. J., Lu, X. F., Luo, Q., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Qu, J. L, Ren, X. Q., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xu, Y. P., Yang, R., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: A link between magnetars and fast radio burst (FRB) sources has finally been established. In this context, one of the open issues is whether/which sources of extra galactic FRBs exhibit X/gamma-ray outbursts and whether it is correlated with radio activity. We aim to constrain possible X/gamma-ray burst activity from one of the nearest extragalactic FRB sources currently known over a broad energy range, by looking for bursts over a range of timescales and energies that are compatible with being powerful flares from extragalactic magnetars. We followed up the as-yet nearest extragalactic FRB source at a mere 149 Mpc distance, the periodic repeater FRB180916.J0158+65, during the active phase on February 4-7, 2020, with the Insight-Hard X-ray Modulation Telescope (HXMT). Taking advantage of the combination of broad band, large effective area, and several independent detectors available, we searched for bursts over a set of timescales from 1 ms to 1.024 s with a sensitive algorithm, that had previously been characterised and optimised. Moreover, through simulations we studied the sensitivity of our technique in the released energy-duration phase space for a set of synthetic flares and assuming different energy spectra. We constrain the possible occurrence of flares in the 1-100 keV energy band to E<10^46 erg for durations <0.1 s over several tens of ks exposure. We can rule out the occurrence of giant flares similar to the ones that were observed in the few cases of Galactic magnetars. The absence of reported radio activity during our observations does not allow us to make any statements on the possible simultaneous high-energy emission., Comment: 10 pages, 3 figures, accepted by A&A
Published: 2020
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18. Insight-HXMT firm detection of the highest energy fundamental cyclotron resonance scattering feature in the spectrum of GRO J1008-57

Author: Ge, M. Y., Ji, L., Zhang, S. N., Santangelo, A., Liu, C. Z., Doroshenko, V., Staubert, R., Qu, J. L., Zhang, S., Lu, F. J., Song, L. M., Li, T. P., Tao, L., Xu, Y. P., Cao, X. L., Chen, Y., Bu, Q. C., Cai, C., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, L. J., Wang, W. S., Wang, Y. D., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, H., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., Zhou, D. K., Zhou, J. F., Zhuang, R. L., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on the observation of the accreting pulsar GRO J1008-57 performed by Insight-HXMT at the peak of the source's 2017 outburst. Pulsations are detected with a spin period of 93.283(1) s. The pulse profile shows double peaks at soft X-rays, and only one peak above 20 keV. The spectrum is well described by the phenomenological models of X-ray pulsars. A cyclotron resonant scattering feature is detected with very high statistical significance at a centroid energy of $E_{\rm cyc}=90.32_{-0.28}^{+0.32}$ keV, for the reference continuum and line models, HIGHECUT and GABS respectively. Detection is very robust with respect to different continuum models. The line energy is significantly higher than what suggested from previous observations, which provided very marginal evidence for the line. This establishes a new record for the centroid energy of a fundamental cyclotron resonant scattering feature observed in accreting pulsars. We also discuss the accretion regime of the source during the Insight-HXMT observation., Comment: 8 pages, 3 figures, accepted for publication in ApJL
Published: 2020
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19. HXMT Identification of a non-thermal X-ray burst from SGR J1935+2154 and with FRB 200428

Author: Li, C. K., Lin, L., Xiong, S. L., Ge, M. Y., Li, X. B., Li, T. P., Lu, F. J., Zhang, S. N., Tuo, Y. L., Nang, Y., Zhang, B., Xiao, S., Chen, Y., Song, L. M., Xu, Y. P., Liu, C. Z., Jia, S. M., Cao, X. L., Qu, J. L., Zhang, S., Gu, Y. D., Liao, J. Y., Zhao, X. F., Tan, Y., Nie, J. Y., Zhao, H. S., Zheng, S. J., Zheng, Y. G., Luo, Q., Cai, C., Li, B., Xue, W. C., Bu, Q. C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, G., Li, M. S., Li, W., Li, X., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Ma, X., Meng, B., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tao, L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xu, H., Yang, J. W., Yang, S., Yang, Y. J., Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Yue, Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Zhi, Zhang, Z. L., Zhou, D. K., Zhou, J. F., Zhu, Y., Zhu, Y. X., and Zhuang, R. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: Fast radio bursts (FRBs) are short pulses observed in radio band from cosmological distances. One class of models invoke soft gamma-ray repeaters (SGRs), or magnetars, as the sources of FRBs. Some radio pulses have been observed from some magnetars, however, no FRB-like events had been detected in association any magnetar burst, including one giant flare. Recently, a pair of FRB-like bursts (FRB 200428 hereafter) separated by milliseconds (ms) were detected from the general direction of the Galactic magnetar SGR J1935+2154. Here we report the detection of a non-thermal X-ray burst in the 1-250 keV energy band with the Insight-HXMT satellite, which we identify as emitted from SGR J1935+2154. The burst showed two hard peaks with a separation of 34 ms, broadly consistent with that of the two bursts in FRB 200428. The delay time between the double radio and X-ray peaks is about 8.57 s, fully consistent with the dispersion delay of FRB 200428. We thus identify the non-thermal X-ray burst is associated with FRB 200428 whose high energy counterpart is the two hard peaks in X-ray. Our results suggest that the non-thermal X-ray burst and FRB 200428 share the same physical origin in an explosive event from SGR J1935+2154., Comment: 24 pages, 9 figures, 6 tables; initial submission to a journal on May 9th, 2020. Significant changes include updated localization and detailed spectral evolution of the X-ray burst, and better determination of the two narrow X-ray peaks corresponding to the two radio pulses. Conclusions are strengthened. Nature Astronomy online on Feb. 18, 2021
Published: 2020
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20. Insight-HXMT insight into switch of the accretion mode: the case of the X-ray pulsar 4U 1901+03

Author: Tuo, Y. L., Ji, L., Tsygankov, S. S., Mihara, T., Song, L. M., Ge, M. Y., Nabizadeh, A., Tao, L., Qu, J. L., Zhang, Y., Zhang, S., Zhang, S. N., Bu, Q. C., Chen, L., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, F. J., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y. F., Zhang, Y. J., Zhang, Y. H., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., Zhou, D. K., Zhou, J. F., Zhu, Y. X., Zhu, Y., and Zhuang, R. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We use the In data collected during the 2019 outburst from X-ray pulsar 4U 1901+03 to complement the orbital parameters reported by Fermi/GBM. Using the Insight-HXMT, we examine the correlation between the derivative of the intrinsic spin frequency and bolometric flux based on accretion torque models. It was found that the pulse profiles significantly evolve during the outburst. The existence of two types of the profile's pattern discovered in the Insight-HXMT data indicates that this source experienced transition between a super-critical and a sub-critical accretion regime during its 2019 outburst. Based on the evolution of the pulse profiles and the torque model, we derive the distance to 4U 1901+03 as 12.4+-0.2 kpc., Comment: 8 pages, 5 figures, accepted by JHEAP
Published: 2020

21. The evolution of the broadband temporal features observed in the black-hole transient MAXI J1820+070 with Insight-HXMT

Author: Wang, Yanan, Ji, Long, Zhang, S. N., Méndez, Mariano, Qu, J. L., Maggi, Pierre, Ge, M. Y., Qiao, Erlin, Tao, L., Zhang, S., Altamirano, Diego, Zhang, L., Ma, X., Lu, F. J., Li, T. P., Huang, Y., Zheng, S. J., Chen, Y. P., Chang, Z., Tuo, Y. L., Gungor, C., Song, L. M., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Bu, Q. C., Cai, C., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. D., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zhou, D. K., Zhou, J. F., Zhuang, R. L., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We study the evolution of the temporal properties of MAXI 1820+070 during the 2018 outburst in its hard state from MJD 58190 to 58289 with Insight-HXMT in a broad energy band 1-150 keV. We find different behaviors of the hardness ratio, the fractional rms and time lag before and after MJD 58257, suggesting a transition occurred at around this point. The observed time lags between the soft photons in the 1-5 keV band and the hard photons in higher energy bands, up to 150 keV, are frequency-dependent: the time lags in the low-frequency range, 2-10 mHz, are both soft and hard lags with a timescale of dozens of seconds but without a clear trend along the outburst; the time lags in the high-frequency range, 1-10 Hz, are only hard lags with a timescale of tens of milliseconds; first increase until around MJD 58257 and decrease after this date. The high-frequency time lags are significantly correlated to the photon index derived from the fit to the quasi-simultaneous NICER spectrum in the 1-10 keV band. This result is qualitatively consistent with a model in which the high-frequency time lags are produced by Comptonization in a jet., Comment: Accepted for publication in ApJ
Published: 2020
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22. Discovery of delayed spin-up behavior following two large glitches in the Crab pulsar, and the statistics of such processes

Author: Ge, M. Y., Zhang, S. N., Lu, F. J., Li, T. P., Yuan, J. P., Zheng, X. P., Huang, Y., Zheng, S. J., Chen, Y. P., Chang, Z., Tuo, Y. L., Cheng, Q., Güngör, C., Song, L. M., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Zhang, S., Qu, J. L., Bu, Q. C., Cai, C., Chen, G., Chen, L., Chen, M. Z., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Hao, L. F., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, C. J., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, D., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Li, Z. X., Liu, Z. Y., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Tao, L., Wang, C., Wang, G. F., Wang, J., Wang, J. B., Wang, M., Wang, N., Wang, W. S., Wang, Y. D., Wang, Y. S., Wen, X. Y., Wen, Z. G., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, Y. H., Yan, W. M., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Yue, Y. L., Zhang, A. M., Zhang, C. M., Zhang, D. P., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, W., Zhou, D. K., Zhou, J. F., Zhou, X., Zhuang, R. L., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Glitches correspond to sudden jumps of rotation frequency ($\nu$) and its derivative ($\dot{\nu}$) of pulsars, the origin of which remains not well understood yet, partly because the jump processes of most glitches are not well time-resolved. There are three large glitches of the Crab pulsar, detected in 1989, 1996 and 2017, which were found to have delayed spin-up processes before the normal recovery processes. Here we report two additional glitches of the Crab pulsar occurred in 2004 and 2011 for which we discovered delayed spin up processes, and present refined parameters of the largest glitch occurred in 2017. The initial rising time of the glitch is determined as $<0.48$ hour. We also carried out a statistical study of these five glitches with observed spin-up processes. The two glitches occurred in 2004 and 2011 have delayed spin-up time scales ($\tau_{1}$) of $1.7\pm0.8$\,days and $1.6\pm0.4$\,days, respectively. We find that the $\Delta{\nu}$ vs. $|\Delta{\dot\nu}|$ relation of these five glitches is similar to those with no detected delayed spin-up process, indicating that they are similar to the others in nature except that they have larger amplitudes. For these five glitches, the amplitudes of the delayed spin-up process ($|\Delta{\nu}_{\rm d1}|$) and recovery process ($\Delta{\nu}_{\rm d2}$), their time scales ($\tau_{1}$, $\tau_{2}$), and permanent changes in spin frequency ($\Delta{\nu}_{\rm p}$) and total frequency step ($\Delta{\nu}_{\rm g}$) have positive correlations. From these correlations, we suggest that the delayed spin-up processes are common for all glitches, but are too short and thus difficult to be detected for most glitches., Comment: 25 pages, 8 figures
Published: 2020
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23. Switches between accretion structures during flares in 4U 1901+03

Author: Ji, L., Ducci, L., Santangelo, A., Zhang, S., Suleimanov, V., Tsygankov, S., Doroshenko, V., Nabizadeh, A., Zhang, S. N., Ge, M. Y., Tao, L., Bu, Q. C., Qu, J. L., Lu, F. J., Chen, L., Song, L. M., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. X., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Yan-Ji, Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Yi, Zhang, Y. F., Zhang, Y. J., Zhang, Y. H., Zhang, Yue, Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, D. K., Zhou, J. F., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on our analysis of the 2019 outburst of the X-ray accreting pulsar 4U 1901+03 observed with Insight-HXMT and NICER. Both spectra and pulse profiles evolve significantly in the decaying phase of the outburst. Dozens of flares are observed throughout the outburst. They are more frequent and brighter at the outburst peak. We find that the flares, which have a duration from tens to hundreds of seconds, are generally brighter than the persistent emission by a factor of $\sim$ 1.5. The pulse profile shape during the flares can be significantly different than that of the persistent emission. In particular, a phase shift is clearly observed in many cases. We interpret these findings as direct evidence of changes of the pulsed beam pattern, due to transitions between the sub- and super-critical accretion regimes on a short time scale. We also observe that at comparable luminosities the flares' pulse profiles are rather similar to those of the persistent emission. This indicates that the accretion on the polar cap of the neutron star is mainly determined by the luminosity, i.e., the mass accretion rate., Comment: 11 pages, 8 figures, accepted for publication in MNRAS
Published: 2020
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24. Joint Analysis of Energy and RMS Spectra from MAXI J1535-571 with Insight-HXMT

Author: Kong, L. D., Zhang, S., Chen, Y. P., Ji, L., Zhang, S. N., Yang, Y. R., Tao, L., Ma, X., Qu, J. L., Lu, F. J., Bu, Q. C., Chen, L., Song, L. M., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. X., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, H., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Y. H., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., Zhou, D. K., Zhou, J. F., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: A new black hole X-ray binary (BHXRB) MAXI J1535-571 was discovered by MAXI during its outburst in 2017. Using observations taken by the first Chinese X-ray satellite, the Hard X-ray Modulation Telescope (dubbed as Insight-HXMT), we perform a joint spectral analysis (2-150 keV) in both energy and time domains. The energy spectra provide the essential input for probing the intrinsic Quasi-Periodic Oscillation (QPO) fractional rms spectra (FRS). Our results show that during the intermediate state, the energy spectra are in general consistent with those reported by Swift/XRT and NuSTAR. However, the QPO FRS become harder and the FRS residuals may suggest the presence of either an additional power-law component in the energy spectrum or a turn-over in the intrinsic QPO FRS at high energies.
Published: 2020

25. Diagnostic of the spectral properties of Aquila X-1 by Insight-HXMT snapshots during the early propeller phase

Author: Güngör, C., Ge, M. Y., Zhang, S., Santangelo, A., Zhang, S. N., Lu, F. J., Zhang, Y., Chen, Y. P., Tao, L., Yang, Y. J., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Ji, L., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Luo, Q., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, Y. P., Yang, J. W., Yang, S., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, D. K., Zhou, J. F., Zhu, Y., and Zhu, Y. X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We study the 2018 outburst of Aql X-1 via the monitor of all sky X-ray image (MAXI) data. We show that the outburst starting in February 2018 is a member of short-low class in the frame of outburst duration and the peak count rate although the outburst morphology is slightly different from the other fast-rise-exponential-decay (FRED) type outbursts with a milder rising stage. We study the partial accretion in the weak propeller stage of Aql X-1 via the MAXI data of the 2018 outburst. We report on the spectral analysis of 3 observations of Aquila X-1 obtained by Insight - hard X-ray modulation telescope (Insight-HXMT) during the late decay stage of the 2018 outburst. We discuss that the data taken by Insight-HXMT is just after the transition to the weak propeller stage. Our analysis shows the necessity of a comptonization component to take into account the existence of an electron cloud resulting photons partly up-scattered., Comment: 8 pages, 4 figures, accepted for publication in JHEAp
Published: 2019

26. $Insight$-HXMT study of the timing properties of Sco X-1

Author: Jia, S. M., Bu, Q. C., Qu, J. L., Lu, F. J., Zhang, S. N., Huang, Y., Ma, X., Tao, L., Xiao, G. C., Zhang, W., Chen, L., Song, L. M., Zhang, S., Li, T. B., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jiang, L. H., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Y. J., Yin, Q. Q., Yi, Q. B., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, D. K., Zhou, J. F., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: We present a detailed timing study of the brightest persistent X-ray source Sco X-1 using the data collected by the Hard X-ray Modulation Telescope ($Insight$-HXMT) from July 2017 to August 2018. A complete $Z$-track hardness-intensity diagram (HID) is obtained. The normal branch oscillations (NBOs) at $\sim$ 6 Hz in the lower part of the normal branch (NB) and the flare branch oscillations (FBOs) at $\sim$ 16 Hz in the beginning part of the flaring branch (FB) are found in observations with the Low Energy X-ray Telescope (LE) and the Medium Energy X-ray Telescope (ME) of $Insight$-HXMT, while the horizontal branch oscillations (HBOs) at $\sim$ 40 Hz and the kilohertz quasi-periodic oscillations (kHz QPOs) at $\sim$ 800 Hz are found simultaneously up to 60 keV for the first time on the horizontal branch (HB) by the High Energy X-ray Telescope (HE) and ME. We find that for all types of the observed QPOs, the centroid frequencies are independent of energy, while the root mean square (rms) increases with energy; the centroid frequencies of both the HBOs and kHz QPOs increase along the $Z$-track from the top to the bottom of the HB; and the NBOs show soft phase lags increasing with energy. A continuous QPO transition from the FB to NB in $\sim$ 200 s are also detected. Our results indicate that the non-thermal emission is the origin of all types of QPOs, the innermost region of the accretion disk is non-thermal in nature, and the corona is nonhomogeneous geometrically.
Published: 2019

27. Insight-HXMT observation on 4U~1608--52: evolving spectral properties of a bright type-I X-ray burst

Author: Chen, Y. P., Zhang, S., Zhang, S. N., Ji, L., Kong, L. D., Santangelo, A., Qu, J. L., Lu, F. J., Li, T. P., Song, L. M., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Bu, Q. C., Cai, C., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liu, J. Y. Liao G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Yang-Ji, Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Yi., Zhang, Y. F., Zhang, Y. J., Zhang, Yue., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, D. K., Zhou, J. F., Zhu, Y., and Zhu, Y. X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The evidences for the influence of thermonuclear (type-I) X-ray bursts upon the surrounding environments in neutron star low-mass X-ray binaries (LMXB) were detected previously via spectral and timing analyses. Benefitting from a broad energy coverage of Insight-HXMT, we analyze one photospheric radius expansion (PRE) burst, and find an emission excess at soft X-rays. Our spectral analysis shows that, such an excess is not likely relevant to the disk reflection induced by the burst emission and can be attributed to an enhanced pre-burst/persistent emission. We find that the burst and enhanced persistent emissions sum up to exceed Eddington luminosity by $\sim$ 40 percentages. We speculate that the enhanced emission is from a region beyond the PRE radius, or through the Comptonization of the corona., Comment: accepted by JHEA(Journal of High Energy Astrophysics)
Published: 2019

28. Insight-HXMT observations of 4U~1636-536: Corona cooling revealed with single short type-I X-ray burst

Author: Chen, Y. P., Zhang, S., Zhang, S. N., Ji, L., Kong, L. D., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Hu, W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, F. J., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Qu, J. L., Sai, N., Song, L. M., Sun, L., Tan, Y., Tao, L., Tao, W. H., Tuo, Y. L., Wang, G. F., Wang, H. Y., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Xu, Y. P., Yan, L. L., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., hang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zheng, S. J., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Corona cooling was detected previously from stacking a series of short type-I bursts occurred during the low/had state of atoll outburst. Type-I bursts are hence regarded as sharp probe to our better understanding on the basic property of the corona. The launch of the first Chinese X-ray satellite Insight-HXMT has large detection area at hard X-rays which provide almost unique chance to move further in this research field. We report the first detection of the corona cooling by Insight-HXMT from single short type-I burst showing up during {\bf flare} of 4U 1636-536. This type-I X-ray burst has a duration of $\sim$13 seconds and hard X-ray shortage is detected with significance 6.2~$\sigma$ in 40-70 keV. A cross-correlation analysis between the lightcurves of soft and hard X-ray band, shows that the corona shortage lag the burst emission by 1.6 $\pm$1.2~s. These results are consistent with those derived previously from stacking a large amount of bursts detected by RXTE/PCA within a series of {\bf flares} of 4U 1636-536. Moreover, the broad bandwidth of Insight-HXMT allows as well for the first time to infer the burst influence upon the continuum spectrum via performing the spectral fitting of the burst, which ends up with the finding that hard X-ray shortage appears at around 40 keV in the continuum spectrum. These results suggest that the evolution of the corona along with the outburst{\bf /flare} of NS XRB may be traced via looking into a series of embedded type-I bursts by using Insight-HXMT., Comment: published in 2018, ApJL,864, L30
Published: 2019
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29. Timing analysis of 2S 1417-624 observed with NICER and Insight-HXMT

Author: Ji, L., Doroshenko, V., Santangelo, A., Gungor, C., Zhang, S., Ducci, L., Zhang, S. -N., Ge, M. -Y., Qu, L. J., Chen, Y. P., Bu, Q. C., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Hu, W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, F. J., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Xu, Y. P., Yang, Y. R., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zheng, S. J., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present a study of timing properties of the accreting pulsar 2S 1417-624 observed during its 2018 outburst, based on Swift/BAT, Fermi/GBM, Insight-HXMT and NICER observations. We report a dramatic change of the pulse profiles with luminosity. The morphology of the profile in the range 0.2-10.0keV switches from double to triple peaks at $\sim2.5$ $\rm \times 10^{37}{\it D}_{10}^2\ erg\ s^{-1}$ and from triple to quadruple peaks at $\sim7$ $\rm \times 10^{37}{\it D}_{10}^2\ erg\ s^{-1}$. The profile at high energies (25-100keV) shows significant evolutions as well. We explain this phenomenon according to existing theoretical models. We argue that the first change is related to the transition from the sub to the super-critical accretion regime, while the second to the transition of the accretion disc from the gas-dominated to the radiation pressure-dominated state. Considering the spin-up as well due to the accretion torque, this interpretation allows to estimate the magnetic field self-consistently at $\sim7\times 10^{12}$G., Comment: 7 pages, 4 figures, 1 tables, accepted for publication in MNRAS
Published: 2019
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30. Constant cyclotron line energy in Hercules X-1 -- Joint Insight-HXMT and NuSTAR observations

Author: Xiao, G. C., Ji, L., Staubert, R., Ge, M. Y., Zhang, S., Zhang, S. N., Santangelo, A., Ducci, L., Liao, J. Y., Guo, C. C., Li, X. B., Zhang, W., Qu, J. L., Lu, F. J., Li, T. P., Song, L. M., Xu, Y. P., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Gungor, C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, S. X., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiong, S. L., Yang, J. W., Yang, S., Yang, Y. J., Yin, Q. B., Yin, Q. Q., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, J. F., Zhu, Y., and Zhu, Y. X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The long-term evolution of the centroid energy of the CRSF in Her X-1 is still a mystery. We report a new measurement from a campaign between {\sl Insight}-HXMT and {\sl NuSTAR} performed in February 2018. Generally, the two satellites show well consistent results of timing and spectral properties. The joint spectral analysis confirms that the previously observed long decay phase has ended, and that the line energy instead keeps constant around 37.5 keV after flux correction.
Published: 2019

31. Measurement of the cosmic-ray proton spectrum from 40 GeV to 100 TeV with the DAMPE satellite

Author: 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: Astrophysics - High Energy Astrophysical Phenomena
Abstract: 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 two and a half years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time an experiment directly measures the cosmic ray protons up to ~100 TeV with a high statistics. The measured spectrum confirms the spectral hardening 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., Comment: 37 pages, 5 figures, published in Science Advances
Published: 2019
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32. Hot disk of the Swift J0243.6+6124 revealed by Insight-HXMT

Author: Doroshenko, V., Zhang, S. N., Santangelo, A., Ji, L., Tsygankov, S., Mushtukov, A., Qu, L. J., Zhang, S., Ge, M. Y., Chen, Y. P., Bu, Q. C., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, Guo, C. C., Han, D. W., Hu, W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, F. J., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Xu, Y. P., Yang, Y. R., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zheng, S. J., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on analysis of observations of the bright transient X-ray pulsar \src obtained during its 2017-2018 giant outburst with Insight-HXMT, \emph{NuSTAR}, and \textit{Swift} observatories. We focus on the discovery of a sharp state transition of the timing and spectral properties of the source at super-Eddington accretion rates, which we associate with the transition of the accretion disk to a radiation pressure dominated (RPD) state, the first ever directly observed for magnetized neutron star. This transition occurs at slightly higher luminosity compared to already reported transition of the source from sub- to super-critical accretion regime associate with onset of an accretion column. We argue that this scenario can only be realized for comparatively weakly magnetized neutron star, not dissimilar to other ultra-luminous X-ray pulsars (ULPs), which accrete at similar rates. Further evidence for this conclusion is provided by the non-detection of the transition to the propeller state in quiescence which strongly implies compact magnetosphere and thus rules out magnetar-like fields., Comment: Submitted to MNRAS
Published: 2019
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33. In-orbit demonstration of X-ray pulsar navigation with the Insight-HXMT satellite

Author: Zheng, S. J., Zhang, S. N., Lu, F. J., Wang, W. B., Gao, Y., Li, T. P., Song, L. M., Ge, M. Y., Han, D. W., Chen, Y., Xu, Y. P., Cao, X. L., Liu, C. Z., Zhang, S., Qu, J. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Gungor, C., Guo, C. C., Hu, W., Huang, Y., Huo, J., Ji, J. F., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G, Sai, N., Shang, R. C., Sun, L., Tan, Y., Tao, L., Tao, W., Tuo, Y. L., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Yan, L. L., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: In this work, we report the in-orbit demonstration of X-ray pulsar navigation with Insight-Hard X-ray Modulation Telescope (Insight-HXMT), which was launched on Jun. 15th, 2017. The new pulsar navigation method 'Significance Enhancement of Pulse-profile with Orbit-dynamics' (SEPO) is adopted to determine the orbit with observations of only one pulsar. In this test, the Crab pulsar is chosen and observed by Insight-HXMT from Aug. 31th to Sept. 5th in 2017. Using the 5-day-long observation data, the orbit of Insight-HXMT is determined successfully with the three telescopes onboard - High Energy X-ray Telescope (HE), Medium Energy X-ray Telescope (ME) and Low Energy X-ray Telescope (LE) - respectively. Combining all the data, the position and velocity of the Insight-HXMT are pinpointed to within 10 km (3 sigma) and 10 m/s (3 sigma), respectively., Comment: Accepted by the Astrophysical Journal Supplement
Published: 2019
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34. The on-orbit calibration of DArk Matter Particle Explorer

Author: 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 Benedittis, A., De Mitri, I., Ding, M., 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., 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, 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, 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., 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. 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, 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 - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment
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
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35. Insight-HXMT observations of the New Black Hole Candidate MAXI J1535-571: timing analysis

Author: Huang, Y., Qu, J. L., Zhang, S. N., Bu, Q. C., Chen, Y. P., Tao, L., Zhang, S., Lu, F. J., Li, T. P., Song, L. M., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Chang, H. -K., Yu, W. f., Weng, S. S., Hou, X., Kong, A. K. H., Xie, F. G., Zhang, G. B., ZHOU, J. F., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Gungor, C., Guo, C. C., Han, D. W., Hu, W., Huo, J., Ji, J. F., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G, Sai, N., Shang, R. C., Sun, L., Tan, Y., Tao, W., Tuo, Y. L., Wang, G. F., Wang, H. Y., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Yan, L. L., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zheng, S. J., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the X-ray timing results of the new black hole candidate (BHC) MAXI J1535-571 during its 2017 outburst from Hard X-ray Modulation Telescope (\emph{Insight}-HXMT) observations taken from 2017 September 6 to 23. Following the definitions given by \citet{Belloni2010}, we find that the source exhibits state transitions from Low/Hard state (LHS) to Hard Intermediate state (HIMS) and eventually to Soft Intermediate state (SIMS). Quasi-periodic oscillations (QPOs) are found in the intermediate states, which suggest different types of QPOs. With the large effective area of \emph{Insight}-HXMT at high energies, we are able to present the energy dependence of the QPO amplitude and centroid frequency up to 100 keV which is rarely explored by previous satellites. We also find that the phase lag at the type-C QPOs centroid frequency is negative (soft lags) and strongly correlated with the centroid frequency. By assuming a geometrical origin of type-C QPOs, the source is consistent with being a high inclination system., Comment: 12 pages, 11 figures, Sumbitted to ApJ
Published: 2018
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36. Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons

Author: 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., 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, 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, High Energy Physics - Experiment, High Energy Physics - Phenomenology
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
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37. The DArk Matter Particle Explorer mission

Author: 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, 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., 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., Lü, 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., and Zimmer, S.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
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., Comment: 45 pages, including 29 figures and 6 tables. Published in Astropart. Phys
Published: 2017
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38. Transmembrane Protease TMPRSS4 Promotes the Formation and Development of Mismatch Repair Deficient Colon Cancer Liver Metastasis

Author: Yang, Y. S., Wen, D., and Zhao, X. F.
Published: 2021
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39. HXMT identification of a non-thermal X-ray burst from SGR J1935+2154 and with FRB 200428

Author: Li, C. K., Lin, L., Xiong, S. L., Ge, M. Y., Li, X. B., Li, T. P., Lu, F. J., Zhang, S. N., Tuo, Y. L., Nang, Y., Zhang, B., Xiao, S., Chen, Y., Song, L. M., Xu, Y. P., Liu, C. Z., Jia, S. M., Cao, X. L., Qu, J. L., Zhang, S., Gu, Y. D., Liao, J. Y., Zhao, X. F., Tan, Y., Nie, J. Y., Zhao, H. S., Zheng, S. J., Zheng, Y. G., Luo, Q., Cai, C., Li, B., Xue, W. C., Bu, Q. C., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, G., Li, M. S., Li, W., Li, X., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Ma, X., Meng, B., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tao, L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xu, H., Yang, J. W., Yang, S., Yang, Y. J., Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Yue, Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Zhi, Zhang, Z. L., Zhou, D. K., Zhou, J. F., Zhu, Y., Zhu, Y. X., and Zhuang, R. L.
Published: 2021
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40. Nascent Rotational Distribution of CO2(0000, J) States from Collisions with Highly Vibrationally Excited Na2.

Author: Zhao, X. F., Yu, Z. L., Wang, S. Y., Qin, C., Shen, Y. F., and Dai, K.
Subjects: *INELASTIC collisions, *STIMULATED emission, *ENERGY transfer, *FLUORESCENCE, *SPECTROMETRY
Abstract: In this work, the high vibrational states of Na2 were excited via stimulated emission pumping. The full-state resolution distribution of molecular scattering of CO2(0000, J), resulting from collisions with excited Na2 X¹ Σ+g (v'= 33 and 45), was also investigated. In particular, the scattered CO2(0000, J = 2–80) molecules were found to possess a biexponential rotational distribution. The low- and high-energy distributions were derived by fitting the data by means of a biexponential model. The cold distribution accounted for 80% of the total scattering and was caused by elastic or weakly inelastic collisions. Such collisions might have caused very small rotational excitations in CO2. The hot distribution involved substantial changes in the rotational energy of CO2 and accounted for 20% of the total amount of collisions. The influence of the donor energy on the rotational distribution was shown to be very large; however, for the two types of donor energies, the branches associated with inelastic and elastic collision rates were the same. The nascent translational energy curves for scattered CO2(0000, J = 56–80) were measured via high-resolution transient overtone fluorescence. For every 25% enhancement in donor vibrational energy, the product translational energy of an individual J-state increased by 60%. Additionally, the measured collision rates were found to be weakly dependent on the donor energy. [ABSTRACT FROM AUTHOR]
Published: 2024
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41. Nascent Rotational Distribution of CO2(0000, J) States from Collisions with Highly Vibrationally Excited Na2.

Author: Zhao, X. F., Yu, Z. L., Wang, S. Y., Qin, C., Shen, Y. F., and Dai, K.
Subjects: INELASTIC collisions, STIMULATED emission, ENERGY transfer, FLUORESCENCE, SPECTROMETRY
Abstract: In this work, the high vibrational states of Na2 were excited via stimulated emission pumping. The full-state resolution distribution of molecular scattering of CO2(0000, J), resulting from collisions with excited Na2 X¹ Σ+g (v'= 33 and 45), was also investigated. In particular, the scattered CO2(0000, J = 2–80) molecules were found to possess a biexponential rotational distribution. The low- and high-energy distributions were derived by fitting the data by means of a biexponential model. The cold distribution accounted for 80% of the total scattering and was caused by elastic or weakly inelastic collisions. Such collisions might have caused very small rotational excitations in CO2. The hot distribution involved substantial changes in the rotational energy of CO2 and accounted for 20% of the total amount of collisions. The influence of the donor energy on the rotational distribution was shown to be very large; however, for the two types of donor energies, the branches associated with inelastic and elastic collision rates were the same. The nascent translational energy curves for scattered CO2(0000, J = 56–80) were measured via high-resolution transient overtone fluorescence. For every 25% enhancement in donor vibrational energy, the product translational energy of an individual J-state increased by 60%. Additionally, the measured collision rates were found to be weakly dependent on the donor energy. [ABSTRACT FROM AUTHOR]
Published: 2024
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42. Measurement and analysis of telegraph noise in the acoustoelectric current of shallow-etched quantum point device

Author: Zhao, X F, Zhang, C Y, Tang, L J, Du, J G, Li, X, and Yan, M
Published: 2020
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43. Unique interfacial reaction and so-induced change in mechanical performance of Sn–3.0Ag–0.5Cu/Cu solder joints formed during undercooled and eutectic liquid soldering processes

Author: Zhou, M. B., Zhao, X. F., Yue, W., and Zhang, X. P.
Published: 2019
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44. GRANDMA and HXMT Observations of GRB 221009A: The Standard Luminosity Afterglow of a Hyperluminous Gamma-Ray Burst—In Gedenken an David Alexander Kann

Author: Kann, D. A., primary, Agayeva, S., additional, Aivazyan, V., additional, Alishov, S., additional, Andrade, C. M., additional, Antier, S., additional, Baransky, A., additional, Bendjoya, P., additional, Benkhaldoun, Z., additional, Beradze, S., additional, Berezin, D., additional, Boër, M., additional, Broens, E., additional, Brunier, S., additional, Bulla, M., additional, Burkhonov, O., additional, Burns, E., additional, Chen, Y., additional, Chen, Y. P., additional, Conti, M., additional, Coughlin, M. W., additional, Cui, W. W., additional, Daigne, F., additional, Delaveau, B., additional, Devillepoix, H. A. R., additional, Dietrich, T., additional, Dornic, D., additional, Dubois, F., additional, Ducoin, J.-G., additional, Durand, E., additional, Duverne, P.-A., additional, Eggenstein, H.-B., additional, Ehgamberdiev, S., additional, Fouad, A., additional, Freeberg, M., additional, Froebrich, D., additional, Ge, M. Y., additional, Gervasoni, S., additional, Godunova, V., additional, Gokuldass, P., additional, Gurbanov, E., additional, Han, D. W., additional, Hasanov, E., additional, Hello, P., additional, Hussenot-Desenonges, T., additional, Inasaridze, R., additional, Iskandar, A., additional, Ismailov, N., additional, Janati, A., additional, du Laz, T. Jegou, additional, Jia, S. M., additional, Karpov, S., additional, Kaeouach, A., additional, Kiendrebeogo, R. W., additional, Klotz, A., additional, Kneip, R., additional, Kochiashvili, N., additional, Kunert, N., additional, Lekic, A., additional, Leonini, S., additional, Li, C. K., additional, Li, W., additional, Li, X. B., additional, Liao, J. Y., additional, Logie, L., additional, Lu, F. J., additional, Mao, J., additional, Marchais, D., additional, Ménard, R., additional, Morris, D., additional, Natsvlishvili, R., additional, Nedora, V., additional, Noonan, K., additional, Noysena, K., additional, Orange, N. B., additional, Pang, P. T. H., additional, Peng, H. W., additional, Pellouin, C., additional, Peloton, J., additional, Pradier, T., additional, Pyshna, O., additional, Rajabov, Y., additional, Rau, S., additional, Rinner, C., additional, Rivet, J.-P., additional, Romanov, F. D., additional, Rosi, P., additional, Rupchandani, V. A., additional, Serrau, M., additional, Shokry, A., additional, Simon, A., additional, Smith, K., additional, Sokoliuk, O., additional, Soliman, M., additional, Song, L. M., additional, Takey, A., additional, Tillayev, Y., additional, Ramirez, L. M. Tinjaca, additional, e Melo, I. Tosta, additional, Turpin, D., additional, de Ugarte Postigo, A., additional, Vanaverbeke, S., additional, Vasylenko, V., additional, Vernet, D., additional, Vidadi, Z., additional, Wang, C., additional, Wang, J., additional, Wang, L. T., additional, Wang, X. F., additional, Xiong, S. L., additional, Xu, Y. P., additional, Xue, W. C., additional, Zeng, X., additional, Zhang, S. N., additional, Zhao, H. S., additional, and Zhao, X. F., additional
Published: 2023
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45. Corrosion behavior of X65 steel in gaseous and liquid CO2 transport environments containing multiple impurities and different H2O content.

Author: Yang, W J, Zhao, X F, Sun, C, Xu, X X, and Sun, J B
Published: 2023
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46. Characterization of Starch Synthetic Genes and Starch Granule during Seeds Development between Synthetic Hexaploid Wheat and its Parents

Author: Li, W., Chen, Z. Y., Li, Z., Zhao, X. F., Pu, Z. E., Chen, G. Y., Jiang, Q. T., Wei, Y. M., and Zheng, Y. L.
Published: 2018
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47. IOA, IOCG and affiliated deposits in the Kangdian and Middle Lower Yangtze River Metallogenic Belt, China

Author: Zhao, X -F, primary
Published: 2021
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48. Metasomatic iron and alkali calcic (MIAC) system frameworks: a TGI-6 task force to help de-risk exploration for IOCG, IOA and affiliated primary critical metal deposits

Author: Corriveau, L, primary, Montreuil, J -F, additional, Blein, O, additional, Potter, E, additional, Ansari, M, additional, Craven, J, additional, Enkin, R, additional, Fortin, R, additional, Harvey, B, additional, Hayward, N, additional, Kellett, D, additional, Ouellet, M, additional, Paradis, S, additional, Regis, D, additional, Sappin, A-A, additional, Tschirhart, V, additional, Péloquin, S, additional, Easton, R M, additional, Maity, B, additional, Conliffe, J, additional, Moukhsil, A, additional, Baldwin, G, additional, Neyedley, K, additional, Wade, C, additional, Reid, A, additional, Fabris, A, additional, Hore, S, additional, Robertson, K, additional, Lisitsin, V, additional, Dhnaram, C, additional, Acosta-Góngora, P, additional, Mansur, E, additional, Quentin de Gromard, R, additional, Kesley, D, additional, Korhonen, F, additional, Duuring, P, additional, Ivanic, T, additional, Goad, R, additional, Adlakha, E, additional, Daliran, F, additional, Dare, S, additional, Gervais, F, additional, Huang, X -W, additional, Kiefer, M, additional, Piette-Lauzière, N, additional, Savard, D, additional, and Zhao, X -F, additional
Published: 2021
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49. GRANDMA and HXMT Observations of GRB 221009A: The Standard Luminosity Afterglow of a Hyperluminous Gamma-Ray Burst—In Gedenken an David Alexander Kann

Author: Kann, D. A., Agayeva, S., Aivazyan, V., Alishov, S., Andrade, C. M., Antier, S., Baransky, A., Bendjoya, P., Benkhaldoun, Z., Beradze, S., Berezin, D., Boër, M., Broens, E., Brunier, S., Bulla, M., Burkhonov, O., Burns, E., Chen, Y., Chen, Y. P., Conti, M., Coughlin, M. W., Cui, W. W., Daigne, F., Delaveau, B., Devillepoix, H. A. R., Dietrich, T., Dornic, D., Dubois, F., Ducoin, J.-G., Durand, E., Duverne, P.-A., Eggenstein, H.-B., Ehgamberdiev, S., Fouad, A., Freeberg, M., Froebrich, Dirk, Ge, M. Y., Gervasoni, S., Godunova, V., Gokuldass, P., Gurbanov, E., Han, D. W., Hasanov, E., Hello, P., Hussenot-Desenonges, T., Inasaridze, R., Iskandar, A., Ismailov, N., Janati, A., du Laz, T. Jegou, Jia, S. M., Karpov, S., Kaeouach, A., Kiendrebeogo, R. W., Klotz, A., Kneip, R., Kochiashvili, N., Kunert, N., Lekic, A., Leonini, S., Li, C. K., Li, W., Li, X. B., Liao, J. Y., Logie, L., Lu, F. J., Mao, J., Marchais, D., Ménard, R., Morris, D., Natsvlishvili, R., Nedora, V., Noonan, K., Noysena, K., Orange, N. B., Pang, P. T. H., Peng, H. W., Pellouin, C., Peloton, J., Pradier, T., Pyshna, O., Rajabov, Y., Rau, S., Rinner, C., Rivet, J.-P., Romanov, F. D., Rosi, P., Rupchandani, V. A., Serrau, M., Shokry, A., Simon, A., Smith, K., Sokoliuk, O., Soliman, M., Song, L. M., Takey, A., Tillayev, Y., Ramirez, L. M. Tinjaca, e Melo, I. Tosta, Turpin, D., de Ugarte Postigo, A., Vanaverbeke, S., Vasylenko, V., Vernet, D., Vidadi, Z., Wang, C., Wang, J., Wang, L. T., Wang, X. F., Xiong, S. L., Xu, Y. P., Xue, W. C., Zeng, X., Zhang, S. N., Zhao, H. S., Zhao, X. F., Kann, D. A., Agayeva, S., Aivazyan, V., Alishov, S., Andrade, C. M., Antier, S., Baransky, A., Bendjoya, P., Benkhaldoun, Z., Beradze, S., Berezin, D., Boër, M., Broens, E., Brunier, S., Bulla, M., Burkhonov, O., Burns, E., Chen, Y., Chen, Y. P., Conti, M., Coughlin, M. W., Cui, W. W., Daigne, F., Delaveau, B., Devillepoix, H. A. R., Dietrich, T., Dornic, D., Dubois, F., Ducoin, J.-G., Durand, E., Duverne, P.-A., Eggenstein, H.-B., Ehgamberdiev, S., Fouad, A., Freeberg, M., Froebrich, Dirk, Ge, M. Y., Gervasoni, S., Godunova, V., Gokuldass, P., Gurbanov, E., Han, D. W., Hasanov, E., Hello, P., Hussenot-Desenonges, T., Inasaridze, R., Iskandar, A., Ismailov, N., Janati, A., du Laz, T. Jegou, Jia, S. M., Karpov, S., Kaeouach, A., Kiendrebeogo, R. W., Klotz, A., Kneip, R., Kochiashvili, N., Kunert, N., Lekic, A., Leonini, S., Li, C. K., Li, W., Li, X. B., Liao, J. Y., Logie, L., Lu, F. J., Mao, J., Marchais, D., Ménard, R., Morris, D., Natsvlishvili, R., Nedora, V., Noonan, K., Noysena, K., Orange, N. B., Pang, P. T. H., Peng, H. W., Pellouin, C., Peloton, J., Pradier, T., Pyshna, O., Rajabov, Y., Rau, S., Rinner, C., Rivet, J.-P., Romanov, F. D., Rosi, P., Rupchandani, V. A., Serrau, M., Shokry, A., Simon, A., Smith, K., Sokoliuk, O., Soliman, M., Song, L. M., Takey, A., Tillayev, Y., Ramirez, L. M. Tinjaca, e Melo, I. Tosta, Turpin, D., de Ugarte Postigo, A., Vanaverbeke, S., Vasylenko, V., Vernet, D., Vidadi, Z., Wang, C., Wang, J., Wang, L. T., Wang, X. F., Xiong, S. L., Xu, Y. P., Xue, W. C., Zeng, X., Zhang, S. N., Zhao, H. S., and Zhao, X. F.
Abstract: Object GRB 221009A is the brightest gamma-ray burst (GRB) detected in more than 50 yr of study. In this paper, we present observations in the X-ray and optical domains obtained by the GRANDMA Collaboration and the Insight Collaboration. We study the optical afterglow with empirical fitting using the GRANDMA+HXMT-LE data sets augmented with data from the literature up to 60 days. We then model numerically using a Bayesian approach, and we find that the GRB afterglow, extinguished by a large dust column, is most likely behind a combination of a large Milky Way dust column and moderate low-metallicity dust in the host galaxy. Using the GRANDMA+HXMT-LE+XRT data set, we find that the simplest model, where the observed afterglow is produced by synchrotron radiation at the forward external shock during the deceleration of a top-hat relativistic jet by a uniform medium, fits the multiwavelength observations only moderately well, with a tension between the observed temporal and spectral evolution. This tension is confirmed when using the augmented data set. We find that the consideration of a jet structure (Gaussian or power law), the inclusion of synchrotron self-Compton emission, or the presence of an underlying supernova do not improve the predictions. Placed in the global context of GRB optical afterglows, we find that the afterglow of GRB 221009A is luminous but not extraordinarily so, highlighting that some aspects of this GRB do not deviate from the global known sample despite its extreme energetics and the peculiar afterglow evolution.
Published: 2023

50. Pressure-induced magnetic transformations in Cd3As2+MnAs hybrid composite

Author: Arslanov, T. R., primary, Saypulaeva, L. A., additional, Alibekov, A. G., additional, Zhao, X. F., additional, Ril, A. I., additional, and Marenkin, S. F., additional
Published: 2022
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