[vsnet-grb-info 17427] GRB 160107A: MAXI/GSC detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18839
SUBJECT: GRB 160107A: MAXI/GSC detection
DATE:    16/01/08 02:25:37 GMT
FROM:    Yujin E. Nakagawa at JAXA  <nakagawa.yujin at jaxa.jp>

Y. E. Nakagawa (JAXA),  H. Negoro (Nihon U.), M. Serino (RIKEN), S. Ueno, H. Tomida,
S. Nakahira, M. Ishikawa (JAXA), T. Mihara, M. Sugizaki, M. Shidatsu, J. Sugimoto,
T. Takagi, M. Matsuoka (RIKEN), N. Kawai, M. Arimoto, T. Yoshii, Y. Tachibana, Y. Ono,
T. Fujiwara (Tokyo Tech), Y. Kawakubo, A. Yoshida, T. Sakamoto, H. Ohtsuki (AGU),
H. Tsunemi, R. Imatani (Osaka U.), M. Nakajima, K. Tanaka, T. Masumitsu (Nihon U.),
Y. Ueda, T. Kawamuro, T. Hori, A. Tanimoto (Kyoto U.),
Y. Tsuboi, S. Kanetou, Y. Nakamura, R. Sasaki (Chuo U.),
M. Yamauchi, D. Itoh, K. Furuya (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
22:19:56 UT on 2016 January 7. Assuming that the source flux was constant over the transit,
we obtain the source position at (R.A., Dec) = (299.670 deg, 6.413 deg) = (19 58 40, +06 24 46) (J2000)
with a statistical 90% C.L. elliptical error region with long and short radii of 0.20 deg and 0.15 deg,
respectively. The roll angle of long axis from the north direction is 151.0 deg counterclockwise.
There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
The X-ray flux averaged over the scan was 366 +- 42 mCrab (4-10keV, 1 sigma error).
Without assumptions on the source constancy, we obtain a rectangular error box
for the transient source with the following corners:
(298.905 deg, 6.966 deg) = (19 55 37, +06 57 57) (J2000)
(299.190 deg, 7.260 deg) = (19 56 45, +07 15 36) (J2000)
(300.076 deg, 6.261 deg) = (20 00 18, +06 15 38) (J2000)
(299.789 deg, 5.968 deg) = (19 59 09, +05 58 03) (J2000)
There was no significant excess flux in the previous transit at 20:47 UT on 2016 January 7
and in the next transit at 23:52 UT on 2016 January 7 with an upper limit of 20 mCrab for each.

For more information: http://maxi.riken.jp/alert/novae/7394729601/7394729601.htm