Swift Observations of GRB 170524B

S.D. Barthelmy (GSFC), A. Cholden-Brown (PSU) and J.D. Gropp (PSU) for the Swift team

1. Introduction

At 10:40:40 UT on 2017-05-24, the Swift Burst Alert Telescope (BAT) triggered on GRB 170524B (trigger=754265) (Barthelmy et al. GCN Circ. 21142). However, on-board analysis was truncated by a pre-planned slew to a scheduled target. Table 1 contains the best reported positions from Swift.

Table 2 is a summary of GCN Circulars about this GRB from observatories other than Swift.

Standard analysis products for this burst are available at http://gcn.gsfc.nasa.gov/swift_gnd_ana.html.

2. BAT Observations and Analysis

BAT refined results are not available.

3. XRT Observations and Analysis

XRT refined results are not available.

4. UVOT Observations and Analysis

Analysis of the UVOT data was reported by Gropp et al. (GCN Circ. 21168). Table 3 gives preliminary magnitudes using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc., 1358, 373). No correction has been made for the expected extinction in the Milky Way corresponding to a reddening of EB-V of 0.19 mag. in the direction of the GRB (Schlegel et al. 1998).

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
06h03m28.49s -17°04'58.7" 0.4" UVOT-refined Gropp et al. GCN Circ. 21168
06h03m28.36s -17°04'57.8" 2.3" XRT-final UKSSDC
06h03m28.33s -17°04'58.2" 2.30" XRT GCN Circ. 21150
06h03m27s -17°05'11" 3' BAT-initial Barthelmy et al. GCN Circ. 21142

Table 1. Positions from the Swift instruments.

Band Authors GCN Circ. Subject Observatory Notes
Optical Podesta et al. 21147 MASTER-OAFA observations MASTER upper limits
Gamma-ray Frederiks et al. 21148 Konus-Wind observation Konus-Wind Epeak=766 (-74,+87) keV

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

Filter Tstart(s) Tstop(s) Exp(s) Mag
white 120431 126833 1297 19.89± 0.08
white 274703 286595 2027 21.11± 0.23

Table 3. UVOT observations reported by Gropp et al. (GCN Circ. 21168). The start and stop times of the exposures are given in seconds since the BAT trigger. The preliminary 3-σ upper limits are given. No correction has been made for extinction in the Milky Way.

May 31, 2017