A search for thermal X-ray signatures in gamma-ray bursts - II. The Swift sample

TY - JOUR

T1 - A search for thermal X-ray signatures in gamma-ray bursts - II. The Swift sample

AU - Sparre, Martin

AU - Starling, Rhaana L.C.

PY - 2012/12/21

Y1 - 2012/12/21

N2 - In several gamma-ray bursts (GRBs) excess emission, in addition to the standard synchrotron afterglow spectrum, has been discovered in the early-time X-ray observations. It has been proposed that this excess comes from blackbody emission, which may be related to the shock breakout of a supernova in the GRBs progenitor star. This hypothesis is supported by the discovery of excess emission in several GRBs with an associated supernova. Using mock spectra we show that it is only likely to detect such a component, similar to the one proposed in GRB 101219B, at low redshift and in low absorption environments. We also perform a systematic search for blackbody components in all the GRBs observed with the Swift satellite and find six bursts (GRBs 061021, 061110A, 081109, 090814A, 100621A and 110715A) with possible blackbody components. Under the assumption that their excess emission is due to a blackbody component we present radii, temperatures and luminosities of the emitting components. We also show that detection of blackbody components only is possible in a fraction of the Swift bursts.

AB - In several gamma-ray bursts (GRBs) excess emission, in addition to the standard synchrotron afterglow spectrum, has been discovered in the early-time X-ray observations. It has been proposed that this excess comes from blackbody emission, which may be related to the shock breakout of a supernova in the GRBs progenitor star. This hypothesis is supported by the discovery of excess emission in several GRBs with an associated supernova. Using mock spectra we show that it is only likely to detect such a component, similar to the one proposed in GRB 101219B, at low redshift and in low absorption environments. We also perform a systematic search for blackbody components in all the GRBs observed with the Swift satellite and find six bursts (GRBs 061021, 061110A, 081109, 090814A, 100621A and 110715A) with possible blackbody components. Under the assumption that their excess emission is due to a blackbody component we present radii, temperatures and luminosities of the emitting components. We also show that detection of blackbody components only is possible in a fraction of the Swift bursts.

U2 - 10.1111/j.1365-2966.2012.221858.x

DO - 10.1111/j.1365-2966.2012.221858.x

M3 - Journal article

SN - 0035-8711

VL - 427

SP - 2965

EP - 2974

JO - Royal Astronomical Society. Monthly Notices

JF - Royal Astronomical Society. Monthly Notices

IS - 4

ER -