MAXI/GSC detection of a renewed X-ray activity of the Be transient X-ray pulsar KS 1947+300

ATel #5438; A. Kawagoe (Chuo U.), T. Mihara (RIKEN), H. Negoro, M. Nakajima (Nihon U.), S. Nakahira, S. Ueno, H. Tomida, M. Kimura, M. Ishikawa, Y. E. Nakagawa (JAXA),M. Sugizaki, M. Morii, M. Serino, J. Sugimoto, T. Takagi, M. Matsuoka (RIKEN),N. Kawai, R. Usui, K. Ishikawa, T. Yoshii (Tokyo Tech), A. Yoshida, T. Sakamoto, Y. Nakano (AGU), H. Tsunemi, M. Sasaki (Osaka U.), H. Sakakibara, K. Fukushima, T. Onodera, K. Suzuki (Nihon U.),Y. Ueda, M. Shidatsu, T. Kawamuro (Kyoto U.), Y. Tsuboi, M. Higa (Chuo U.), M. Yamauchi, K. Yoshidome, Y. Ogawa, H. Yamada (Miyazaki U.),K. Yamaoka (Nagoya U.) report on behalf of the MAXI team:
on 3 Oct 2013; 02:54 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Tatehiro Mihara (mihara@crab.riken.jp)

Tweet

The MAXI/GSC nova alert system triggered an X-ray transient source at 01:15:36 UT on 2013 October 02 (trigger ID 6567223727, MAXI x-ray-star ML. No.233). Assuming a constant X-ray flux during each scan transit, we obtained the source position at (R.A., Dec) = (297.344 deg, 30.147 deg) with a 90 % C.L. statistical error of 0.38 deg and an additional systematic uncertainty of 0.1 deg (90% containment radius). The position is consistent with that of KS 1947+300 (= GRO J1948+32). This outburst started on around 2013 September 28, and the one-day averaged 2-10 keV flux on 2013 October 02 is approximately 20 mCrab.

KS 1947+300 was discovered with Mir/Kvant on 1989 June 08 (Borozdin et al. 1990), and 18.70 s pulsation was found with CGRO/BASTE in 1994 (Chakrabarty et al. 1995). KS 1947+300 exhibited a giant outburst on 2001 January, reaching about 150 mCrab (Galloway et al. 2004, Naik et al. 2006), and followed by several smaller outbursts. RXTE/ASM, Swift/BAT and MAXI data, however, show no significant outburst from this source after around MJD 53400 (2005 January 30).

The triggered information and the MAXI light curves can be found at the following URLs;
http://www.maxi.riken.jp/alert/novae/6567223727/6567223727.htm
http://maxi.riken.jp/top/index.php?cid=1&jname=J1949+302