The recent discovery of a kilonova from the long duration gamma-ray burst, GRB 211211A, challenges classification schemes based on temporal information alone. Gamma-ray properties of GRB 211211A reveal an extreme event, which stands out among both short and long GRBs. We find very short variations (few ms) in the lightcurve of GRB 211211A and estimate ~1000 for the Lorentz factor of the outflow. We discuss the relevance of the short variations in identifying similar long GRBs resulting from compact mergers. Our findings indicate that in future gravitational wave follow-up campaigns, some long duration GRBs should be treated as possible strong gravitational wave counterparts.
@article{arxiv.2305.12262,
title = {Extreme Variability in a Long Duration Gamma-ray Burst Associated with a Kilonova},
author = {P. Veres and P. N. Bhat and E. Burns and R. Hamburg and N. Fraija and D. Kocevski and R. Preece and S. Poolakkil and N. Christensen and M. A. Bizouard and T. Dal Canton and S. Bala and E. Bissaldi and M. S. Briggs and W. Cleveland and A. Goldstein and B. A. Hristov and C. M. Hui and S. Lesage and B. Mailyan and O. J. Roberts and C. A. Wilson-Hodge},
journal= {arXiv preprint arXiv:2305.12262},
year = {2024}
}