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Title: Searching for the radio remnants of short-duration gamma-ray bursts
ABSTRACT Neutron star mergers produce a substantial amount of fast-moving ejecta, expanding outwardly for years after the merger. The interaction of these ejecta with the surrounding medium may produce a weak isotropic radio remnant, detectable in relatively nearby events. We use late-time radio observations of short duration gamma-ray bursts (sGRBs) to constrain this model. Two samples of events were studied: four sGRBs that are possibly in the local (<200 Mpc) Universe were selected to constrain the remnant non-thermal emission from the sub-relativistic ejecta, whereas 17 sGRBs at cosmological distances were used to constrain the presence of a proto-magnetar central engine, possibly re-energizing the merger ejecta. We consider the case of GRB 170817A/GW170817 and find that in this case the early radio emission may be quenched by the jet blast-wave. In all cases, for ejecta mass range of $${M}_{\rm {ej}}\lesssim 10^{-2}\, (5\times 10^{-2})\, \mathrm{M}_\odot$$, we can rule out very energetic merger ejecta $${E}_{\rm {ej}}\gtrsim 5\times 10^{52}\, (10^{53})\, \rm erg$$, thus excluding the presence of a powerful magnetar as a merger remnant.  more » « less
Award ID(s):
1907975
PAR ID:
10288031
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
500
Issue:
2
ISSN:
0035-8711
Page Range / eLocation ID:
1708 to 1720
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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