MAXI/GSC detection of renewed X-ray activity of the black hole candidate SLX 1746-331
ATel #15937; H. Negoro, Y. Soejima, M. Nakajima, K. Kobayashi, M. Tanaka (Nihon U.), T. Mihara, T. Kawamuro, S. Yamada, 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 (Miyazaki U.), K. Yamaoka (Nagoya U.), Y. Kawakubo (LSU), M. Sugizaki (NAOC), and W. Iwakiri (Chiba U.)
on 8 Mar 2023; 07:31 UT
Credential Certification: Hitoshi Negoro (negoro@phys.cst.nihon-u.ac.jp)
Subjects: X-ray, Black Hole
The MAXI/GSC nova alert system triggered on a bright X-ray transient source at 04:21 UT on 2023 March 8. Assuming that the source flux was constant over five transits from 20:36 on March 7 to 04:21 on March 8, we obtain the source position at
(R.A., Dec) = (267.380 deg, -33.150 deg) = (17 49 31, -33 08 59) (J2000)
with a statistical 90% C.L. elliptical error region with long and short radii of 0.10 deg and 0.09 deg, respectively. The roll angle of the long axis from the north direction is 122.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius). The X-ray flux averaged over the scans was 129 +- 10 mCrab (4.0-10.0keV, 1 sigma error).
The outburst with a soft X-ray spectrum started early on March 7 2023. The source position is well consistent with that of the black hole candidate SLX 1746-331. SLX 1746-331 exhibited outbursts on 2003 (ATel #143, #144), 2007 (ATel #1235), and 2011 (ATel #3098) in the RXTE and MAXI era. The observed peak fluxes of those outbursts were about 400 mCrab, 100 mCrab, and 40 mCrab, respectively. We also tentatively name the source MAXI J1749-331.
Followup observations are encouraged.
MAXI data for SLX 1746-331
