[vsnet-grb-info 17411] GRB 160104B: MAXI/GSC detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18818
SUBJECT: GRB 160104B: MAXI/GSC detection
DATE:    16/01/04 12:54:30 GMT
FROM:    H. Negoro at Nihon U.  <negoro at phys.cst.nihon-u.ac.jp>

Y. Kawakubo (AGU), M. Nakajima, H. Negoro (Nihon U.), M. Serino (RIKEN),
S. Ueno, H. Tomida, S. Nakahira, M. Ishikawa, Y. E. Nakagawa (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),
A. Yoshida, T. Sakamoto, H. Ohtsuki (AGU),
H. Tsunemi, R. Imatani (Osaka U.),
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 10:13:03 UT on on 2016 January 4.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (108.879 deg, 54.865 deg) = (07 15 30, +54 51 54) (J2000)
with a statistical 90% C.L. elliptical error region
with long and short radii of 0.32 deg and 0.29 deg, respectively.
The roll angle of long axis from the north direction is 72.0 deg 
counterclockwise. There is an additional systematic uncertainty of 0.1 deg 
(90% containment radius).
The X-ray flux averaged over the scan was 123 +- 24 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:
(R.A., Dec) = (109.823 deg, 54.028 deg) = (07 19 17, +54 01 40) (J2000)
(R.A., Dec) = (108.777 deg, 53.855 deg) = (07 15 06, +53 51 17) (J2000)
(R.A., Dec) = (107.662 deg, 55.997 deg) = (07 10 38, +55 59 47) (J2000)
(R.A., Dec) = (108.739 deg, 56.218 deg) = (07 14 57, +56 13 04) (J2000)
There was no significant excess flux in the previous transit at UT 08:40 UT 
on 2016 January 4 with an upper limit of 20 mCrab for each.

For more information: http://maxi.riken.jp/alert/novae/7391314067/7391314067.htm