Unraveling the dynamics and kinematics of GRB hosts with high resolution spectroscopy

TL;DR

This paper investigates the detailed kinematic and spatial properties of gamma-ray burst (GRB) host galaxies using high-resolution spectroscopy, revealing outflows and local environments of GRB sites.

Contribution

It provides new insights into the kinematic behavior and local environments of GRB hosts through high-resolution spectral analysis and spatially resolved observations.

Findings

Detection of outflows in GRB 030329 and GRB 060206 hosts.

Resolved the GRB site in nearby hosts, showing star-forming regions.

GRB 060505 occurred in a metal-poor, star-forming environment similar to other long-duration GRB hosts.

Abstract

In the last years the research on GRB host galaxies has proceeded to more detailed studies both using high resolution afterglow spectroscopy and spatially resolved spectra of nearby hosts. High resolution spectra give a detailed picture of the kinematic properties of matter along the line-of-sight in the host. Two afterglow spectra show clear indications for outflows from their host, namely GRB 030329 and GRB 060206, derived from the position of absorption and host emission lines, nonvariability of Mg I and the radiation field calculated from fine-structure line detections. In nearby GRB hosts it is possible to resolve the actual GRB site. GRB 060505, a SN-less GRB, originated in a relatively metal poor, star forming region with similar properties as other long-duration hosts. A similar conclusion is reached for the site of GRB 980425/SN 1998bw.