MAXI/GSC detection of a new X-ray outburst from the direction of the galactic center

ATel #15346; W. Iwakiri(Chuo U.), H. Negoro (Nhon U.), S. Yamada (RIKEN), M. Serino (AGU), M. Nakajima, K. Kobayashi, K. Asakura, K. Seino (Nihon U.), T. Mihara, T. Kawamuro, T. Tamagawa, M. Matsuoka (RIKEN), T. Sakamoto, S. Sugita, H. Hiramatsu, A. Yoshida (AGU), Y. Tsuboi, J. Kohara (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, M. Tominaga, T. Nagatsuka, T. Kurihara (JAXA), Y. Ueda, S. Ogawa, K. Setoguchi, T. Yoshitake, Y. Goto, R. Uematsu, K. Inaba (Kyoto U.), H. Tsunemi (Osaka U.), M. Yamauchi, Y. Nonaka, T. Sato, R. Hatsuda, R. Fukuoka (Miyazaki U.), K. Yamaoka (Nagoya U.), Y. Kawakubo (LSU), M. Sugizaki (NAOC) report on behalf of the MAXI team:
on 24 Apr 2022; 16:08 UT
Credential Certification: Wataru Iwakiri (wataru.iwakiri@riken.jp)

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MAXI/GSC detected an X-ray outburst from the direction of the galactic center.
The outburst started on MJD59688 and peaked on MJD59690 with a peak X-ray luminosity of about 150 mCrab at the 4-10 keV band. It has now decayed to about 100 mCrab.
Assuming that the source flux was constant over the transit, we obtain the source position at
(R.A., Dec) = (266.718 deg, -28.755 deg) = (17 46 52, -28 45 17) (J2000)
with a statistical 90% C.L. elliptical error region with long and short radii of 0.11 deg and 0.08 deg, respectively.
The roll angle of long axis from the north direction is 28.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
There are two known sources in this error region, SAX J1747.0-2853 and 1E1743.1-2843, but the spatial resolution of MAXI does not allow us to determine which source is responsible for the outburst. The Swift/BAT lightcurve shows that the flux of 1E1743.1-2843 seems to be slightly increasing. Since it is also possible that the source is a new source, we tentatively name it MAXI J1746-287.
Followup observations are encouraged to determine the source of this outburst.