GW170817: implications for the local kilonova rate and for surveys from ground-based facilities [HEAP]

http://arxiv.org/abs/1809.04295


We compute the local rate of events similar to GRB 170817A, which has been recently found to be associated with a kilonova (KN) outburst. Our analysis finds an observed rate of such events of R${KN}\sim 352^{+810}{-281}$ Gpc$^{-3}$yr$^{-1}$. After comparing at their face values this density of sGRB outbursts with the much higher density of Binary Neutron Star (BNS) mergers of 1540$^{+3200}_{-1220}$ Gpc$^{-3}$yr$^{-1}$, estimated by LIGO-Virgo collaboration, one can conclude, admittedly with large uncertainty that either only a minor fraction of BNS mergers produces sGRB/KN events or the sGRBs associated with BNS mergers are beamed and observable under viewing angles as large as $\theta$ $\leq$ $40^{\circ}$. Finally we provide preliminary estimates of the number of sGRB/KN events detected by future surveys carried out with present/future ground-based/space facilities, such as LSST, VST, ZTF, SKA and THESEUS.

Read this paper on arXiv…

M. Valle, D. Guetta, E. Cappellaro, et. al.
Thu, 13 Sep 18
52/68

Comments: MNRAS accepted, 6 pages, 1 figure