GRB Properties
Parameters calculated by MPE
| Property | Value | Error (1 σ statistical) |
|---|---|---|
| Trigger Number | ||
| Trigger Time | Sept. 18, 2025, 12:32:18 | |
| Data Timestamp | Sept. 18, 2025, 14:19:14 | |
| Localization Timestamp | Sept. 18, 2025, 14:30:53 | |
| Balrog Ra [deg] | 225.1 | 1.6 |
| Balrog Dec [deg] | -16.3 | 1.3 |
| Error radius 1 σ [deg] | 3.7 | |
| Error radius 2 σ [deg] | 4.3 | |
| Estimated systematic error [deg] | 2 | |
| Fitted Model | cutoff_powerlaw | |
| Spectral Parameter K [photons/cm^2/keV*s] | 2e+02 | 28 |
| Spectral Parameter Index | -2.3 | 0.04 |
| Spectral Parameter XC [keV] | 5e+03 | 4e+03 |
| Satellite Phi [deg] | 50.97 | |
| Satellite Theta [deg] | -1.81 |
Parameters from external Source
| Property | Value |
|---|---|
| Swift Ra [deg] | |
| Swift Dec [deg] | |
| Most likely | None None% |
| Second most likely | None None% |
GRB Location Alert
To circulars@gcn.nasa.gov
GRB 250918A: BALROG localization (Fermi Trigger 779891543 / GRB 250918522)
T. Preis (University of Innsbruck) & J. Greiner (MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
779891543 at 12:32:18 on 18 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) = 225.6 deg
Decl.(2000.0) = -16.2 deg
The 1 sigma statistical error radius is 4.1 deg.
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB250918522/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB250918522/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB250918522/json
GRB 250918A: BALROG localization (Fermi Trigger 779891543 / GRB 250918522)
T. Preis (University of Innsbruck) & J. Greiner (MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
779891543 at 12:32:18 on 18 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) = 225.6 deg
Decl.(2000.0) = -16.2 deg
The 1 sigma statistical error radius is 4.1 deg.
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB250918522/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB250918522/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB250918522/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