A detailed spectral study of GRB 041219A and its host galaxy

作者:Goetz D*; Covino S; Hascoet R; Fernandez Soto A; Daigne F; Mochkovitch R; Esposito P
来源:Monthly Notices of the Royal Astronomical Society, 2011, 413(3): 2173-2183.
DOI:10.1111/j.1365-2966.2011.18290.x

摘要

GRB 041219A is one of the longest and brightest gamma-ray bursts (GRBs) ever observed. It was discovered by the INTEGRAL satellite, and thanks to a precursor happening about 300 s before the bulk of the burst, ground-based telescopes were able to catch the rarely observed prompt emission in the optical and in the near-infrared bands.
Here we present the detailed analysis of its prompt gamma-ray emission, as observed with IBIS onboard INTEGRAL, and of the available X-ray afterglow data collected by X-Ray Telescope onboard Swift. We then present the late-time multiband near-infrared imaging data, collected at the Telescopio Nazionale Galileo (TNG) and the Canada-France-Hawaii Telescope (CFHT), that allowed us to identify the host galaxy of the GRB as an underluminous, irregular galaxy of similar to 5 x 109 M-circle dot at best-fitting redshift of z = 0.31+0.54(-0.26).
We model the broad-band prompt optical to gamma-ray emission of GRB 041219A within the internal shock model. We were able to reproduce the spectra and light curve invoking the synchrotron emission of relativistic electrons accelerated by a series of propagating shock waves inside a relativistic outflow. On the other hand, it is less easy to simultaneously reproduce the temporal and spectral properties of the infrared data.

  • 出版日期2011-5
  • 单位中国地震局