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arXiv · 2010.02767

Fermi/GBM View of the 2019 and 2020 Burst Active Episodes of SGR J1935+2154

Lin Lin·Ersin Gogus·Oliver J. Roberts·Matthew G. Baring·Chryssa Kouveliotou·Yuki Kaneko·Alexander J. van der Horst·George Younes
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Abstract

We present temporal and time-integrated spectral analyses of 148 bursts from the latest activation of SGR J1935+2154, observed with Fermi/GBM from October 4th 2019 through May 20th 2020, excluding a ~130 s segment with a very high burst density on April 27th 2020. The 148 bursts presented here, are slightly longer and softer than bursts from earlier activations of SGR J1935+2154, as well as from other magnetars. The long-term spectral evolution trend is interpreted as being associated with an increase in the average plasma loading of the magnetosphere during bursts. We also find a trend of increased burst activity from SGR J1935+2154 since its discovery in 2014. Finally, we find no association of typical radio bursts with X-ray bursts from the source; this contrasts the association of FRB 200428 with an SGR J1935+2154 X-ray burst, to date unique among the magnetar population.

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Lin Lin, Ersin Gogus, Oliver J. Roberts, Matthew G. Baring, Chryssa Kouveliotou, Yuki Kaneko, Alexander J. van der Horst, George Younes. 2020-10-06. Fermi/GBM View of the 2019 and 2020 Burst Active Episodes of SGR J1935+2154. https://doi.org/10.3847/2041-8213%2Fabbefe

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