[vsnet-grb-info 17563] GRB 160206A: MAXI/GSC detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18993
SUBJECT: GRB 160206A: MAXI/GSC detection
DATE:    16/02/06 07:01:50 GMT
FROM:    Motoko Suzuki at RIKEN  <motoko at crab.riken.jp>

K. Furuya (Miyazaki U.) , Nakahira, M.(JAXA), M. Nakajima (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 Y. Kawakubo (AGU),
H. Tsunemi, R. Imatani (Osaka U.),
H. Negoro (Nihon 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, (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 02:52:43 UT on on 2016 Feburary 6.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (132.696 deg, -36.099 deg) = (08 50 47, -36 05 56) (J2000)
with a statistical 90% C.L. elliptical error region
with long and short radii of 0.33 deg and 0.3 deg, respectively.
The roll angle of long axis from the north direction is 23.0 deg counterclockwise.
There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
The X-ray flux averaged over the scan was 125 +- 26 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) = (132.055 deg, -35.576 deg) = (08 48 13, -35 34 32) (J2000)
(R.A., Dec) = (132.787 deg, -35.291 deg) = (08 51 08, -35 17 28) (J2000)
(R.A., Dec) = (133.399 deg, -36.778 deg) = (08 53 35, -36 46 40) (J2000)
(R.A., Dec) = (132.642 deg, -37.044 deg) = (08 50 34, -37 02 39) (J2000)
There was no significant excess flux in the previous transit at UT 01:20
and in the next transit at 04:25 UT with an upper limit of 20 mCrab for each.