NICER Magnetar Burst Catalog

Che-Yen Chu;Chin-Ping Hu;Teruaki Enoto;George A. Younes;Rachael Stewart;Zaven Arzoumanian;Wynn C. G. Ho;Zorawar Wadiasingh;Andrea Sanna;Sebastien Guillot;Gaurava K. Jaisawal;Matthew G. Baring;Marlon L. Bause;Tolga Güver;Chryssa Kouveliotou;Alex Van Kooten;Keith C. Gendreau

2026-01-01

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Abstract

In this paper, we present a comprehensive catalog of short bursts from magnetars based on 8 yr of NICER observations. A total of 1130 bursts were identified from 14 sources, with the sample dominated by SGR 1935+2154, which accounts for 76% of all detected bursts. We analyzed burst durations, spectral properties, and their correlations across multiple sources. Bursts from SGR 1935+2154 exhibit significantly longer durations, with a mean of 317 ms, compared to a mean of 23 ms for bursts from other magnetars. Two microsecond-scale bursts were detected for the first time, originating from 1E 1048.1−5937 and CXOU J010043.1−721134. Spectral analysis in the 0.5–8 keV range using both blackbody and power-law models shows that bursts with higher fluences have harder spectra. In contrast, correlations between burst duration and spectral parameters are weak or absent. This catalog provides a valuable dataset for studying magnetar short bursts, enabling future modeling efforts and improving our understanding of the diversity and physical mechanisms of magnetar bursts.