Location of GRB201218177

GRB Properties

Parameters calculated by MPE

Property	Value	Error (1 σ statistical)
Trigger Number	629957660
Trigger Time	Dec. 18, 2020, 04:14:15
Data Timestamp	Dec. 18, 2020, 04:23:41
Localization Timestamp	Dec. 18, 2020, 04:43:45
Balrog Ra [deg]	287.4	0.3
Balrog Dec [deg]	26.8	0.3
Error radius 1 σ [deg]	0.4
Error radius 2 σ [deg]	0.7
Estimated systematic error [deg]	1
Fitted Model	cutoff_powerlaw
Spectral Parameter K [photons/cm^2/keV*s]	6.9	0.22
Spectral Parameter Index	-0.89	0.0082
Spectral Parameter XC [keV]	5e+02	1e+01
Satellite Phi [deg]	-15.78
Satellite Theta [deg]	-7.92

Parameters from external Source

Property	Value
Swift Ra [deg]
Swift Dec [deg]
Most likely	GRB 80.0%
Second most likely	CYG_X1 15.0%

GRB Location Alert

GRB 201218A: BALROG localization (Fermi Trigger 629957660 / GRB 201218177)

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
629957660 at 04:14:15 on 18 Dec. 2020 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) = 287.38+/-0.29 deg
Decl.(2000.0) = 26.80+/-0.30 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB201218177/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB201218177/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB201218177/json