Triggering the Untriggered: The First Einstein Probe-Detected Gamma-Ray Burst 240219A and Its Implications

التفاصيل البيبلوغرافية
العنوان: Triggering the Untriggered: The First Einstein Probe-Detected Gamma-Ray Burst 240219A and Its Implications
المؤلفون: Yin, Yi-Han Iris, Zhang, Bin-Bin, Yang, Jun, Sun, Hui, Zhang, Chen, Shao, Yi-Xuan, Hu, You-Dong, Zhu, Zi-Pei, Xu, Dong, An, Li, Gao, He, Wu, Xue-Feng, Zhang, Bing, Castro-Tirado, Alberto Javier, Pandey, Shashi B., Rau, Arne, Lei, Weihua, Xie, Wei, Ghirlanda, Giancarlo, Piro, Luigi, O'Brien, Paul, Troja, Eleonora, Jonker, Peter, Yu, Yun-Wei, An, Jie, Chen, Run-Chao, Chen, Yi-Jing, Dong, Xiao-Fei, Eyles-Ferris, Rob, Fan, Zhou, Fu, Shao-Yu, Fynbo, Johan P. U., Gao, Xing, Huang, Yong-Feng, Jiang, Shuai-Qing, Jiang, Ya-Hui, Julakanti, Yashaswi, Kuulkers, Erik, Lao, Qing-Hui, Li, Dongyue, Ling, Zhi-Xing, Liu, Xing, Liu, Yuan, Mou, Jia-Yu, Varun, Wei, Daming, Wu, Qinyu, Yadav, Muskan, Yang, Yu-Han, Yuan, Weimin, Zhang, Shuang-Nan
سنة النشر: 2024
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - High Energy Astrophysical Phenomena
الوصف: The Einstein Probe (EP) achieved its first detection and localization of a bright X-ray flare, EP240219a, on February 19, 2024, during its commissioning phase. Subsequent targeted searches triggered by the EP240219a alert identified a faint, untriggered gamma-ray burst (GRB) in the archived data of Fermi/GBM, Swift/BAT, Insight-HXMT/HE and INTEGRAL/SPI-ACS. The EP/WXT light curve reveals a long duration of approximately 160 seconds with a slow decay, whereas the Fermi/GBM light curve shows a total duration of approximately 70 seconds. The peak in the Fermi/GBM light curve occurs slightly later with respect to the peak seen in the EP/WXT light curve. Our spectral analysis shows that a single cutoff power-law model effectively describes the joint EP/WXT-Fermi/GBM spectra in general, indicating coherent broad emission typical of GRBs. The model yielded a photon index of $\sim -1.70 \pm 0.05$ and a peak energy of $\sim 257 \pm 134$ keV. After detection of GRB 240219A, long-term observations identified several candidates in optical and radio wavelengths, none of which was confirmed as the afterglow counterpart during subsequent optical and near-infrared follow-ups. The analysis of GRB 240219A classifies it as an X-ray rich GRB with a high peak energy, presenting both challenges and opportunities for studying the physical origins of X-ray flashes (XRFs), X-ray rich GRBs (XRRs), and classical GRBs (C-GRBs). Furthermore, linking the cutoff power-law component to non-thermal synchrotron radiation suggests that the burst is driven by a Poynting flux-dominated outflow.
Comment: 14 pages, 8 figures, 3 tables
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2407.10156
رقم الأكسشن: edsarx.2407.10156
قاعدة البيانات: arXiv