Soft X-ray prompt emission from the high-redshift gamma-ray burst EP240315a

作者：Y. Liu, H. Sun, D. Xu, D. Svinkin, J. Delaunay, N. Tanvir, H. Gao, C. Zhang, Y. Chen, X.-F. Wu, B. Zhang, W. Yuan, J. An, G. Bruni, D. Frederiks, G. Ghirlanda, J.-W. Hu, A. Li, C. Li, J. Li, D. Malesani, L. Piro, G. Raman, R. Ricci, E. Troja, S. Vergani, Q. Wu, J. Yang, B.-B. Zhang, Z.-P. Zhu, A. de Ugarte Postigo, A. G. Demin, D. Dobie, Z. Fan, S. Fu, J. Fynbo, J. Geng, G. Gianfagna, Y.-D. Hu, Y. Huang, S.-Q. Jiang, P. Jonker, Y. Julakanti, J. Kennea, A. Kokomov, E. Kuulkers, W. Lei, J. K. Leung, A. Levan, D. Li, Y. Li, S. Littlefair, X. Liu, A. L. Lysenko, Y.-N. Ma, A. Martin-Carrillo, P. O’Brien, T. Parsotan, J. Quirola-Vásquez, A. Ridnaia, S. Ronchini, A. Rossi, D. Mata-Sánchez, B. Schneider, Rong-Feng Shen, A. L. Thakur, A. Tohuvavohu, M. Torres, A. Tsvetkova, M. Ulanov, J.-J. Wei, D. Xiao, Y.-H. I. Yin, M. Bai, V. Burwitz, Z. Cai, F.-S. Chen, H. Chen, T. Chen, W. Chen, Y. Chen, Y-H. Chen, H. Cheng, B. Cordier, C. Cui, W. Cui, Y. Dai, Z. Dai, J. Eder, R. Eyles-Ferris, D.-W. Fan, C. Feldman, H. Feng, Z. Feng, P. Friedrich, X. Gao, J.F. Gonzalez, J. Guan, D. Han, J. Han, D. Hou, H. Hu, T. Hu, M.-H. Huang, J. Huo, I. Hutchinson, Z. Ji, S. Jia, Z. Jia, B. Jiang, C. Jin, G. Jin, J. Jin, A. Keereman, H. Lerman, J.-F. Li, L. Li, M. Li, W. Li, Z.-D. Li, T.-Y. Lian, E. Liang, Z. Ling, C. Liu, H. Liu, H. Liu, M.-J. Liu, Y.-R. Liu, F. Lu, H. Lü, L. Luo, F. Ma, J. Ma, J. Mao, X. Mao, M. McHugh, N. Meidinger, K. Nandra, J. Osborne, H. Pan, X. Pan, M. Ravasio, A. Rau, N. Rea, U. Rehman, Jeremy S. Sanders, A. Santovincenzo, Liming Song, J. Su, L.-J. Sun, S.-L. Sun, X. Sun, Y. Tan, Q.-J. Tang, Y. Tao, J. Tong, C. Wang, H. Wang, J. Wang, L. Wang, W. Wang, X. Wang, X. Wang, Y. Wang, Y.-S. Wang, D. Wei, R. Willingale, S. Xiong, H.T. Xu, J.-J. Xu, X.P. Xu, Y. Xu, Z. Xu, C. Xue, Y. Xue, A.-L. Yan, F. Yang, H.-N. Yang, X. Yang, Y. Yang, Y.W. Yu, J. Zhang, M. Zhang, S.-N. Zhang, W.D. Zhang, W. Zhang, Y. Zhang, Z. Zhang, Z. Zhang, Z.L. Zhang, D. Zhao, H. Zhao, X. Zhao, Z.-J. Zhao, L.-X. Zhou, Y.-l. Zhou, Y. Zhu, Z.-C. Zhu, X. Zuo · 发表于：Nature Astronomy · 年份：2025 · DOI：10.1038/s41550-024-02449-8 · 被引用次数：41

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 (~3,600°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. The death of massive stars has traditionally been discovered by explosive events in the gamma-ray band. Liu et al. show that the sensitive wide-field monitor on board Einstein Probe can reveal a weak soft-X-ray signal much earlier than gamma rays.