MAXI/GSC detection of X-ray rebrightening of GRS 1915+105

ATel #15968; S. Yamada (RIKEN), M. Nakajima, H. Negoro, K. Kobayashi, M. Tanaka, Y. Soejima (Nihon U.), T. Mihara, T. Kawamuro, T. Tamagawa, M. Matsuoka (RIKEN), T. Sakamoto, M. Serino, S. Sugita, H. Hiramatsu, H. Nishikawa, A. Yoshida (AGU), Y. Tsuboi, J. Kohara, S. Urabe, S. Nawa, N. Nemoto (Chuo U.), M. Shidatsu, M. Iwasaki (Ehime U.), N. Kawai, M. Niwano, R. Hosokawa, Y. Imai, N. Ito, Y. Takamatsu (Tokyo Tech), S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, T. Kurihara (JAXA), Y. Ueda, S. Ogawa, K. Setoguchi, T. Yoshitake, K. Inaba, Y. Nakatani (Kyoto U.), M. Yamauchi, T. Sato, R. Hatsuda, R. Fukuoka, Y. Hagiwara, Y. Umeki, Y. Otsuki (Miyazaki U.), K. Yamaoka (Nagoya U.), Y. Kawakubo (LSU), M. Sugizaki (NAOC), and W. Iwakiri (Chiba U.)
on 31 Mar 2023; 08:32 UT
Credential Certification: Hitoshi Negoro (negoro@phys.cst.nihon-u.ac.jp)

Tweet

The MAXI/GSC nova alert system triggered on the rebrightening of the microquasar GRS 1915+105 at 17:10 UT on 2023 March 30. The source flux at the scan was 0.18 +/- 0.04 ph/cm2/s (~80 mCrab), 0.31 +/- 0.04 ph/cm2/s (~140 mCrab), and 0.16 +/- 0.04 ph/cm2/s (~400 mCrab) in the 2-4 keV, 4-10 keV, and 10-20 keV band, respectively. After that, the GSC detected the source at 18:44, 20:17, and 21:50 on March 30.

After the sudden decrease in X-ray flux in 2018 (ATel #11828), the GSC sometimes detected short-term activity from GRS 1915+105 as reported on 2019 May 14 (ATel #12761), 2019 May 21 (ATel #12787), 2020 February 13 (ATel #13478), 2020 April 20 (ATel #13652), and on 2021 July 9 (e.g., ATel #14792).
Recently, Trushkin et al. (ATel #15964) reported X-ray and radio flares around 2023 March 25 detected by Swift/BAT and RATAN-600. We note that the GSC could not observe the source region from 2023 March 16 to the scan transit time at 14:25 on March 30.

MAXI data for GRS 1915+105