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arXiv · 1708.01352

X-ray upper limits of GW151226 with MAXI

Motoko Serino·Nobuyuki Kawai·Hitoshi Negoro·Tatehiro Mihara·Takahiro Masumitsu·Satoshi Nakahira
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Abstract

The error region of the the gravitational-wave (GW) event GW151226 was observed with Monitor of All-sky X-ray Image (MAXI). MAXI was operated at the time of GW151226, and continuously observed to 4 minutes after the event. MAXI covered about 84% of the 90 percent error region of the GW event during the first 92 minutes orbit after the event. No significant X-ray transient was detected in the GW error region. A typical 3-$σ$ GSC upper limit for a scan is 1.2 $\times 10^{-9}$ ergs cm$^{-2}$ s$^{-1}$ in the 2-20 keV. The auto-detection (MAXI nova-search) systems detected a short excess event with a low significance (2.85$σ$) from 5257 s to 5260 s after the GW trigger. Finally, we discuss the sensitivity of MAXI to long X-ray emissions of short gamma-ray bursts, which are expected to accompany GW events.

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Motoko Serino, Nobuyuki Kawai, Hitoshi Negoro, Tatehiro Mihara, Takahiro Masumitsu, Satoshi Nakahira. 2017-08-04. X-ray upper limits of GW151226 with MAXI. https://doi.org/10.1093/pasj%2Fpsx086

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