GRB 250917B

Time: 06:27:44
Trigger Number: 1350381
Burst Advocate: Regina Caputo

BAT Data:

RA: a	291.382 19:25:31.7
Dec: a	11.117 11:07:01.2
90% Error Radius: b	1.4
T90: c	0.29
Fluence: d	1.7 (0.2)
1s Peak Photon Flux: e	2.4 (0.3)
Photon Index: f	1.66, PL (0.17)

---

90% error in parentheses,
^a J2000; ^b arcmin; ^c seconds; ^d 10^-7 erg/cm² (15-150 keV); ^e ph/cm²/sec (15-150 keV); ^f PL = simple power-law, CPL = cutoff power-law (15-150 keV)

XRT Data:

RA: a	n/a
Dec: a	n/a
90% Error Radius: b	n/a
Time to First Observation: c	134.2
Early Flux: d	n/a
11 Hour Flux: d	n/a
24 Hour Flux: d	n/a
Initial Temporal Index:	n/a
Spectral Index (Gamma):	n/a
Column Density (NH): e	n/a

---

Note: Please be aware that only the very basic temporal and spectral quantities are reported here. You are strongly encouraged to see the referenced GCN circulars for full details.
^a J2000; ^b arcsec; ^c seconds; ^d 10^-11 erg/cm²/s (0.3-10 keV); ^e 10²¹ cm^-2

» XRT GRB Live Catalogue
» XRT Light Curves
» XRT Spectra

UVOT Data:

RA: a	n/a
Dec: a	n/a
90% Error Radius: b	n/a
Time to First Observation: c	139
V Magnitude:	V>18.1
Other Filter Magnitudes:	B>20.1 U>20.1 UVW1>18.9 UVM2>18.8 UVW2>19.0 White>21.2

---

^a J2000; ^b arcsec; ^c seconds

Comments:

XRT: Three uncatalogued X-ray sources have been detected within the estimated 3-σ Swift-BAT error region (296 arcsec), however none of them is above the RASS limit or shows definitive signs of fading.
UVOT: no detection

References:

BAT: GCN 41848; GCN 41868
XRT: GCN 41848; GCN 41851
UVOT: GCN 41848; GCN 41864
Radio:
Redshift:
Host:
Other: