Search for merger ejecta emission from late time radio observations of short GRBs using GMRT

Understand

Short gamma-ray bursts (GRBs) are the aftermath of compact binary mergers involving neutron stars.

• If the merger remnant is a millisecond magnetar instead of a black hole, a significant proportion of the rotational energy deposited to the emerging ejecta can produce a late-time radio brightening from its interaction with the ambient medium.
• Detection of this late-time radio emission from short GRBs can have profound implications for understanding the physics of the progenitor.
• We report the radio observations of five short GRBs - 050709, 061210, 100625A, 140903A, and 160821B using the Giant Metrewave Radio Telescope (GMRT) at 1250, 610, and 325 MHz frequencies after $\sim$ $2 - 11$ years from the time of the burst.