Swift Observations of GRB 151120A

A.P. Beardmore (U. Leicester) for the Swift team

1. Introduction

Mereghetti et al. (GCN Circ. 18623) reported the GRB detection. A gamma ray burst lasting about 50 s has been detected by IBAS in the IBIS/ISGRI data at 8:22:50 UT of 2015 November 20. Table 1 contains the best reported positions from Swift.

Kruehler et al. (GCN Circ. 18624) reported the position from GROND for the optical afterglow of this GRB. Table 2 is a summary of GCN Circulars about this GRB from observatories other than Swift.

2. BAT Observations and Analysis

BAT did not observe this burst.

3. XRT Observations and Analysis

XRT results are not available.

4. UVOT Observations and Analysis

UVOT results are not available.

Figure 1. The BAT light curve is not available.

XRT light curve

Figure 2. The XRT light curve. Any data from a crosshatched region are not included in the fit.

RA (J2000) Dec (J2000) Error Note Reference
10h28m57.91s -32°31'35.1" 2.2" XRT-final UKSSDC
10h28m57.83s -32°31'34.2" 3.6" XRT Beardmore et al. GCN Circ. 18629

Table 1. Positions from the Swift instruments.

Band Authors GCN Circ. Subject Observatory Notes
Optical Kruehler et al. 18624 GROND optical/NIR afterglow GROND detection
Gamma-ray Mereghetti et al. 18623 A long GRB detected by INTEGRAL INTEGRAL
Gamma-ray von Kienlin 18628 Fermi GBM observation Fermi GBM Epeak=243 (+23/-19) keV
T90=20 seconds
Fluence=9.4±0.3x10-6erg cm-2
(74th percentile for long GRBs)
Gamma-ray Golenetskii et al. 18636 Konus-Wind observation Konus-Wind Fluence=7.20(-1.25,+1.79)x10-6erg cm-2

Table 2. Summary of GCN Circulars from other observatories sorted by band and then circular number.

November 24, 2015