Swift Observations of GRB 140414A

J.R. Cummings (NASA/UMBC), P. D'Avanzo (INAF-OAB) and F.E. Marshall (NASA/GSFC) for the Swift team

1. Introduction

At 2014-04-14T06:06:29, IPN spacecraft triggered on GRB 140414A (Cummings GCN Circ. 16110). 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.

2. BAT Observations and Analysis

The light curve (Figure 1) shows two main peaks each about 0.3 seconds long, the second about 3 times as intense and peaking about 0.3 seconds after the first. T90 is estimated as 0.7 ± 0.1 seconds.

The spectrum is best fit by a simple powerlaw function with a photon index of 0.74 ± 0.18. The fluence in 0.7 seconds was (1.22 ± 0.10) x 10-7 ergs/cm2. This fluence is larger than that of 76% of the short GRBs in the Second BAT GRB Catalog (Sakamoto et al. 2011). Errors are 90% confidence.

3. XRT Observations and Analysis

XRT results are not available.

4. UVOT Observations and Analysis

The Swift/UVOT observed the field of GRB 140414A in the U, White, and V filters starting about 40 ks after the BAT trigger (Marshall et al. GCN Circ. 16114). Because the star tracker failed to lock, stars are trailed in all the images, and the usual UVOT sensitivities are not achieved. 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 0.01 mag. in the direction of the GRB (Schlegel et al. 1998).

Figure 1. The BAT light curve is not available.

RA (J2000) Dec (J2000) Error Note Reference
13h01m14.3s +56°54'06" 4' BAT-refined Cummings GCN Circ. 16111

Table 1. Positions from the Swift instruments.

Band Authors GCN Circ. Subject Observatory Notes
Optical D'Avanzo et al. 16112 TNG optical observations TNG

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 40958 41502 536 >20

Table 3. UVOT observation reported by Marshall et al. (GCN Circ. 16114). The start and stop time of the exposure are given in seconds since the BAT trigger. The preliminary 3-σ upper limit is given. No correction has been made for extinction in the Milky Way.

May 22, 2015