The spatially resolved host of GRB 060505 and implications for the nature of the progenitor

TL;DR

This study analyzes the host galaxy of GRB 060505, revealing a spiral galaxy with a young, low-metallicity star-forming region at the burst site, suggesting a massive star progenitor rather than a compact object merger.

Contribution

It provides the first spatially resolved analysis of GRB 060505's host galaxy, challenging previous assumptions about its progenitor based on burst duration.

Findings

Host galaxy is a spiral galaxy, unusual for long GRBs.

GRB site has intense star formation, low metallicity, and young stellar age.

Results support a massive star progenitor over a compact object merger.

Abstract

We present a study of the host galaxy of the Gamma-Ray Burst (GRB) of May 5 2006 (GRB 060505). The host is spatially resolved in both imaging data and in a long slit spectrum including the GRB site. We find the galaxy to be a Sbc spiral, which is unusual for a long GRB host galaxy. The site of the GRB is considerably different from the rest of the galaxy with intense star formation, low metallicity and a young age. This suggest a massive stellar progenitor rather than a merger of compact objects which has been suggested based on the the relatively short duration of T_90=4s for the prompt emission.