GCN Circular 37261
Subject
GRB 240824B: MAXI/GSC detection
Date
2024-08-24T15:49:41Z (3 months ago)
From
Motoko Serino at Aoyama Gakuin U. <serino@phys.aoyama.ac.jp>
Via
Web form
M. Nakajima (Nihon U.), M. Serino, S. Sugita (AGU),
H. Negoro, Y. Kudo, H. Shibui, K. Takagi, H. Takahashi, K. Tatano, H. Nishio (Nihon U.),
T. Mihara, T. Kawamuro, S. Yamada, S. Wang, T. Tamagawa, N. Kawai, M. Matsuoka (RIKEN),
T. Sakamoto, Y. Kawakubo, H. Hiramatsu, H. Nishikawa, Y. Kondo, A. Yoshida (AGU),
Y. Tsuboi, H. Sugai, N. Nagashima (Chuo U.),
M. Shidatsu, Y. Niida (Ehime U.),
I. Takahashi, M. Niwano, N. Higuchi, Y. Yatsu (Tokyo Tech),
S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, S. Ogawa, M. Kurihara (JAXA),
Y. Ueda, Y. Okada (Kyoto U.),
M. Yamauchi, Y. Otsuki, T. Hasegawa, M. Nishio (Miyazaki U.),
K. Yamaoka (Nagoya U.),
M. Sugizaki (Kanazawa U.),
W. Iwakiri (Chiba U.)
report on behalf of the MAXI team:
The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at
13:10:30 UT on 24 Aug 2024.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (17.672 deg, 2.083 deg) = (01 10 41, +02 04 58) (J2000)
with a statistical 90% C.L. elliptical error region
with long and short radii of 0.27 deg and 0.07 deg, respectively.
The roll angle of long axis from the north direction is 136.0 deg counterclockwise.
There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
This position is within the error of GRB 240824B detected by Fermi GBM (GCN #37260).
The X-ray flux averaged over the scan was 45 +- 15 mCrab
(4.0-10.0keV, 1 sigma error).
There was no significant excess flux in the previous transit at 11:37 UT
and in the next transit at 14:43 UT with an upper limit of 20 mCrab for each.