GRB 121102A

Time: 02:27:02
Trigger Number: 537266
Burst Advocate: Valerio D'Elia

BAT Data:

RA: a	270.896 18:03:35.0
Dec: a	-16.951 -16:57:03.6
90% Error Radius: b	1.0
T90: c	24.7
Fluence: d	19 (1)
1s Peak Photon Flux: e	2.3 (0.2)
Photon Index: f	1.88, PL (0.07)

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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)

BAT Light Curve:

XRT Data:

RA: a	18:03:36.22
Dec: a	-16:57:28.4
90% Error Radius: b	1.4
Time to First Observation: c	47.73
Early Flux: d	345
11 Hour Flux: d	0.033925059
24 Hour Flux: d	0.014773659
Initial Temporal Index:	-3.296
Spectral Index (Gamma):	1.77855
Column Density (NH): e	8.00045

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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	58
V Magnitude:	V>20.0
Other Filter Magnitudes:	B>21.4 U>20.9 UVW1>20.8 UVM2>21.1 UVW2>21.2 White>21.4

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^a J2000; ^b arcsec; ^c seconds

Comments:

This event has all appearances of a GRB: hard BAT spectrum, bright XRT initial detection and fading. Still, we note that the galactic coordinates are l=12 deg, b=2.5 deg, consistent with a galactic origin. We believe it is a GRB, but can not rule out a new galactic transient.
UVOT: no detection

References:

BAT: GCN 13938; GCN 13942
XRT: GCN 13938; GCN 13943; GCN 13945; Evans et al., 2009, MNRAS, 397, 1177
UVOT: GCN 13938; GCN 13948
Radio:
Redshift:
Host:
Other: GCN Report 401.1