GRB 030329: 3 years of radio afterglow monitoring

TL;DR

This study presents a three-year radio monitoring of GRB 030329, revealing detailed insights into the burst's physical parameters and jet nature, and predicts LOFAR's capability to observe similar afterglows in the future.

Contribution

It provides a comprehensive long-term radio dataset of GRB 030329 and models its late-time light curve to forecast LOFAR's potential observations.

Findings

Determined the total burst energy and ambient medium density.

Confirmed the jet nature of the relativistic outflow.

Predicted LOFAR can observe similar GRB afterglows in the non-relativistic phase.

Abstract

Radio observations of gamma-ray burst (GRB) afterglows are essential for our understanding of the physics of relativistic blast waves, as they enable us to follow the evolution of GRB explosions much longer than the afterglows in any other wave band. We have performed a three-year monitoring campaign of GRB 030329 with the Westerbork Synthesis Radio Telescopes (WSRT) and the Giant Metrewave Radio Telescope (GMRT). Our observations, combined with observations at other wavelengths, have allowed us to determine the GRB blast wave physical parameters, such as the total burst energy and the ambient medium density, as well as investigate the jet nature of the relativistic outflow. Further, by modeling the late-time radio light curve of GRB 030329, we predict that the Low-Frequency Array (LOFAR, 30-240 MHz) will be able to observe afterglows of similar GRBs, and constrain the physics of the blast wave during its non-relativistic phase.