GRB Properties
Parameters calculated by MPE
| Property | Value | Error (1 σ statistical) |
|---|---|---|
| Trigger Number | 780029651 | |
| Trigger Time | Sept. 20, 2025, 02:54:06 | |
| Data Timestamp | Sept. 20, 2025, 03:33:13 | |
| Localization Timestamp | Sept. 20, 2025, 03:48:24 | |
| Balrog Ra [deg] | 174.6 | 3.1 |
| Balrog Dec [deg] | 52.8 | 1.5 |
| Error radius 1 σ [deg] | 1.9 | |
| Error radius 2 σ [deg] | 2.5 | |
| Estimated systematic error [deg] | 2 | |
| Fitted Model | cutoff_powerlaw | |
| Spectral Parameter K [photons/cm^2/keV*s] | 34 | 1.5 |
| Spectral Parameter Index | -1.1 | 0.016 |
| Spectral Parameter XC [keV] | 3e+02 | 1e+01 |
| Satellite Phi [deg] | 51.80 | |
| Satellite Theta [deg] | 2.35 |
Parameters from external Source
| Property | Value |
|---|---|
| Swift Ra [deg] | |
| Swift Dec [deg] | |
| Most likely | GRB 96.0% |
| Second most likely | GENERIC_TRANSIENT 3.0% |
GRB Location Alert
To circulars@gcn.nasa.gov
GRB 250920A: BALROG localization (Fermi Trigger 780029651 / GRB 250920121)
T. Preis (University of Innsbruck) & J. Greiner (MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
780029651 at 02:54:06 on 20 Sept. 2025 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 is:
RA(2000.0) = 174.6 deg
Decl.(2000.0) = 52.8 deg
The 1 sigma statistical error radius is 1.9 deg.
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB250920121/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB250920121/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB250920121/json
GRB 250920A: BALROG localization (Fermi Trigger 780029651 / GRB 250920121)
T. Preis (University of Innsbruck) & J. Greiner (MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
780029651 at 02:54:06 on 20 Sept. 2025 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 is:
RA(2000.0) = 174.6 deg
Decl.(2000.0) = 52.8 deg
The 1 sigma statistical error radius is 1.9 deg.
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB250920121/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB250920121/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB250920121/json
GRB Location
J2000 Coordinate Frame
All Corner Plot
J2000 Coordinate Frame
Moll Location Plot
J2000 Coordinate Frame
Satellite
Spectrum Residuals Plot
3D - GRB Location Plot
Satellite Coordiante Frame
Light Curves
