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TITLE:   GCN CIRCULAR
NUMBER:  31032
SUBJECT: GRB 211102B: Fermi GBM Final Real-time Localization
DATE:    21/11/02 14:16:38 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 14:05:35 UT on 2 Nov 2021, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 211102B (trigger 657554740.140466 / 211102587).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 300.9, Dec = -2.6 (J2000 degrees, equivalent to J2000 20h 03m, -2d 36'), with a statistical uncertainty of 1.8 degrees.

The angle from the Fermi LAT boresight is 64.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn211102587/quicklook/glg_skymap_all_bn211102587.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn211102587/quicklook/glg_healpix_all_bn211102587.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn211102587/quicklook/glg_lc_medres34_bn211102587.gif

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TITLE:   GCN CIRCULAR
NUMBER:  31033
SUBJECT: GRB 211102B: BALROG localization (Fermi Trigger 657554740 / GRB 211102587)
DATE:    21/11/02 14:24:49 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

B. Biltzinger, F. Kunzweiler, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
657554740 at 14:05:35 on 02 Nov. 2021 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 315.4+/-3.0 deg
Decl.(2000.0) = 1.5+/-1.5 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB211102587/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB211102587/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB211102587/json

                        

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TITLE:   GCN CIRCULAR
NUMBER:  31035
SUBJECT: GRB 211102B: GECAM detection
DATE:    21/11/03 14:06:08 GMT
FROM:    Chao Zheng at IHEP  <zhengchao97@ihep.ac.cn>

J. C. Liu, S. Xiao, Yi Zhao, S. L. Xiong, C. Cai, J. J. He, Y. Huang, Z. W. Guo, 
C. Y. Li, X. B. Li, J. C. Liu, X. Y. Song, P. Wang, S. L. Xie, W. C. Xue,
Q. B. Yi, Y. Q. Zhang, G. Y. Zhao, X. Y. Zhao, C. Zheng, Y. Q. Du, D. Y. Guo, 
J. Liang, F. J. Lu, Q. Luo, X. Ma, W. X. Peng, R. Qiao, L. M. Song, J. Wang, H. Wu, 
C. W. Wang, P. Zhang, S. N. Zhang, X. L. Zhang, Z. Zhang, S. J. Zheng (IHEP),
report on behalf of GECAM team:

During the commissioning phase, GECAM-B was triggered in-flight by a 
long bright burst, GRB 211102B, at 2021-11-02T14:05:35.350 UTC (denoted as T0), 
which is also observed by Fermi/GBM (GCN #31033).

Its alert data was promptly downlinked to the ground through the short
message service of BeiDou Navigation Satellite System (BDS). The time
latency of the first BeiDou message relative to the trigger time is about 1 minute.

According to the BDS alert data, this burst mainly consists of multiple
pulses with duration of about 20 s.

The GECAM light curve could be found here:
http://twiki.ihep.ac.cn/pub/GECAM/GRBList/211102BLC.png

GECAM-B localized this burst to the following position (J2000): 
Ra: 298.1 deg 
Dec: -2.9 deg
Err: 2.4 deg (1-sigma,statistical only)
The current systematic error of location is estimated to be several degrees 
which could be minimized by the ongoing calibration.

The GECAM preliminary location could be found here: 
http://twiki.ihep.ac.cn/pub/GECAM/GRBList/20211102Bloc.png

Please note that all GECAM results here are preliminary. The final analysis
will be published in journal papers or GECAM online catalog.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor
(GECAM) mission consists of two small satellites (GECAM-A and GECAM-B) in
Low Earth Orbit (600 km, 29 deg), launched on Dec 10, 2020 (Beijing Time),
which was funded by the Chinese Academy of Sciences (CAS).