GCN Circular 18246

Y. E. Nakagawa (JAXA), H. Negoro, (Nihon U.), M. Serino (RIKEN),
M. Ishikawa, S. Nakahira, S. Ueno, H. Tomida,  M. Kimura(JAXA),
T. Mihara, M. Sugizaki,  M. Shidatsu, J. Sugimoto, T. Takagi, M. Matsuoka (RIKEN), 
N. Kawai, Y. Tachibana, T. Yoshii (Tokyo Tech),
A. Yoshida, T. Sakamoto, Y. Kawakubo, H. Ohtsuki (AGU), 
H. Tsunemi, R. Imatani (Osaka U.), M. Nakajima, T. Masumitsu, K. Tanaka (Nihon U.), 
Y. Ueda, T. Kawamuro, T. Hori (Kyoto U.), Y. Tsuboi, S. Kanetou (Chuo U.), 
M. Yamauchi, D. Itoh (Miyazaki U.), K. Yamaoka (Nagoya U.), M. Morii (ISM) 
report on behalf of the MAXI team:

The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at
16:00:50 UT on 7 September 2015. Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (224.845 deg, -47.592 deg) = (14 59 22, -47 35 31) (J2000)
with a 90% C.L. statistical error of 0.06 deg. 
There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
The X-ray flux averaged over the scan was 1464 +- 75 mCrab (4-10keV, 1 sigma error).
There was no significant excess flux in the previous transit at 14:28 UT on 7 September 2015
with an upper limit of 20 mCrab.