Iron K Lines from Gamma Ray Bursts

Preprint
Publisher Website
Google Scholar
  • 30 October 2001
Abstract
We present models for reprocessing of an intense flux of X-rays and gamma rays expected in the vicinity of gamma ray burst sources. We consider the transfer and reprocessing of the energetic photons into observable features in the X-ray band, notably the K lines of iron. Our models are based on the assumption that the gas is sufficiently dense to allow the microphysical processes to be in a steady state, thus allowing efficient line emission with modest reprocessing mass and elemental abundances ranging from solar to moderately enriched. We show that the reprocessing is enhanced by down-Comptonization of photons whose energy would otherwise be too high to absorb on iron, and that pair production can have an effect on enhancing the line production. While "distant" reprocessors such as supernova or wind remnants require Fe abundances much larger than solar to reproduce the observed line luminosities, we show that "nearby" reprocessor models, involving e.g. outer stellar envelopes, can do so with solar or only modestly enriched abundances.

This publication has 0 references indexed in Scilit: