MAXI/GSC detection of a new X-ray transient MAXI J1735-272

ATel #14979; H. Negoro, K. Seino, M. Nakajima, K. Kobayashi, K. Asakura (Nihon U.), T. Mihara, T. Tamagawa, M. Matsuoka (RIKEN), T. Sakamoto, M. Serino, S. Sugita, K. Komachi, A. Yoshida (AGU), Y. Tsuboi, W. Iwakiri, H. Kawai, Y. Okamoto, S. Kitakoga (Chuo U.), M. Shidatsu (Ehime U.), N. Kawai, M. Niwano, R. Hosokawa (Tokyo Tech), S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, M. Tominaga, T. Nagatsuka, T. Kurihara (JAXA), Y. Ueda, S. Yamada, 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.), T. Kawamuro (UDP/NAOJ), K. Yamaoka (Nagoya U.), Y. Kawakubo (LSU), and M. Sugizaki (NAOC)
on 18 Oct 2021; 03:11 UT
Credential Certification: Hitoshi Negoro (negoro@phys.cst.nihon-u.ac.jp)

Tweet

The MAXI/GSC nova alert system triggered on a faint X-ray transient source at 06:22 UT on 2021 October 17. Assuming that the source flux was constant over 7 transits from 04:49 to 18:46 on October 17, we obtain the source position at
(R.A., Dec) = (263.766 deg, -27.231 deg) = (17 35 03, -27 13 51) (J2000)
with a statistical 90% C.L. elliptical error region with long and short radii of 0.40 deg and 0.37 deg, respectively. The roll angle of the long axis from the north direction is 0.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius). The X-ray flux averaged over the scans was 30 +- 7 mCrab (4.0-10.0keV, 1 sigma error).

Currently, the 4-10 keV flux tends to decrease. The source is near the Galactic Center (l, b)=(0.2 deg, 2.9 deg). The position is, however, far from known bright X-ray sources, i.e., 0.56 arc-degree away from the X-ray transient IGR J17329-2731 (Postel et al ATel. #10644), and 0.75 arc-degree from SXL 1735-269. We, therefore, tentatively name the source MAXI J1735-272.

Followup observations are encouraged.

Trigger information about MAXI J1735-272