GRB 240229A
GCN Circular 35904
Subject
GRID detection of GRB 240229A (Updated Report)
Date
2024-03-08T16:54:57Z (2 years ago)
From
GRID Student Team at Tsinghua University <grid@tsinghua.edu.cn>
Via
Web form
Chenyu Wang, Zirui Yang and Longhao Li report on behalf of the GRID Collaboration:
GRID-03B and GRID-04 report the detection of the long-duration GRB 240229A, which was also detected by Fermi/GBM, CALET VZLUSAT-2, GRBAlpha and Glowbug (GCN Circular 35833, 35842, 35872, 35894 and 35897).
The event was triggered with GRID on 2024-02-29 at 14:07:08 UTC and had a double-peak structure. The measured burst duration (T90) in the 30-2000 keV range is approximately 25.0 ± 3.0 seconds.
The time-averaged spectrum of the first peak using GRID-04 realtime data from T+0 to T+10 sec is best fit by a power-law model with a fluence in the 10-1000 keV band is about 3.5259E-05 erg/cm2. The powerlaw index of the time-averaged spectrum is -1.51(-0.06,+0.06). All the quoted errors are at the 1-sigma confidence level.
The GRID light curve of this event can be found at https://mirrors.tuna.tsinghua.edu.cn/GRID/data/GRID-GCN/GRB240229A/GRID_240229A_ltcv.pdf. The GRID spectrum of this event can be found at https://mirrors.tuna.tsinghua.edu.cn/GRID/data/GRID-GCN/GRB240229A/GRID_240229A_spec_pl.pdf.
GRID is a student-led project to monitor the transient gamma-ray sky with multiple detectors onboard different nanosatellites in the era of multi-messenger astronomy. For more information about GRID, please refer to the following references: https://doi.org/10.1007/s10686-019-09636-w and https://doi.org/10.1007/s10686-021-09819-4.
GCN Circular 35903
Subject
GRID detection of GRB 240229A
Date
2024-03-08T16:39:27Z (2 years ago)
From
GRID Student Team at Tsinghua University <grid@tsinghua.edu.cn>
Via
Web form
Chenyu Wang, Zirui Yang and Longhao Li report on behalf of the GRID Collaboration:
GRID-03B and GRID-04 report the detection of the long-duration GRB 240229A, which was also detected by Fermi/GBM, CALET VZLUSAT-2, GRBAlpha and Glowbug (GCN Circular 35833, 35842, 35872, 35894 and 35897).
The event was triggered with GRID on 2024-02-29 at 14:07:08 UTC and had a double-peak structure. The measured burst duration (T90) in the 30-2000 keV range is approximately 25.0 ± 3.0 seconds.
The time-averaged spectrum of the first peak using GRID-04 realtime data from T+0 to T+10 sec is best fit by a power-law model with a fluence in the 10-1000 keV band is about 3.5259E-05 erg/cm2. The powerlaw index of the time-averaged spectrum is -1.51(-0.06,+0.06). All the quoted errors are at the 1-sigma confidence level.
GCN Circular 35897
Subject
GRB 240229A: Glowbug gamma-ray detection
Date
2024-03-07T14:43:24Z (2 years ago)
From
C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>
Via
Web form
C.C. Cheung, R. Woolf, M. Kerr, J.E. Grove (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge, D. Kocevski (MSFC), and M.S. Briggs (UAH) report:
The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 240229A, which was also detected by Fermi/GBM (GCN 35833, 35834), CALET (GCN 35842), INTEGRAL/SPI-ACS, Konus/Wind, BepiColombo (GCN 35870), VZLUSAT-2 (GCN 35872), and GRBAlpha (GCN 35894