Short Gamma Ray Bursts and their Afterglow Signatures in Dense Stellar Systems

Parsons, Rion K.
Ramirez-Ruiz, Enrico
Lee, William H.
Journal Title
Journal ISSN
Volume Title
The hypothesis that short GRBs arise from the coalescence of binary compact stars has recently gained support. With this comes the expectation that the afterglow should bear the characteristic signature of a tenuous intergalactic medium (IGM). However, fits to the observational data suggest that some detected afterglows arise in relatively dense gaseous environments rather than in the low density IGM. Here we show that considering the effect of red giant winds in the core of a star cluster may resolve this paradox if short GRB progenitors are contained in such an environment and close encounters rather than pure gravitational wave emission brings the compact objects together. Clear confirmation is provided here of the important notion that the morphology and visibility of short gamma-ray burst remnants are determined largely by the state of the gas in the cluster's core.
Comment: 9 pages, 3 figures, submitted to ApJ
Astrophysics - High Energy Astrophysical Phenomena