Keck Observations of 160 Gamma-Ray Burst Host Galaxies

TL;DR

This paper reports on a large-scale Keck Observatory survey of over 160 gamma-ray burst host galaxies, providing extensive multi-color imaging, spectroscopy, and a publicly accessible database to advance understanding of GRB environments.

Contribution

It presents the broadest GRB host galaxy survey to date, including diverse GRB sub-classes and a new online database with photometry and redshifts.

Findings

Over 100 host galaxy detections, many previously unreported

Diverse GRB types included, such as short, long, and dark bursts

Preliminary data release with photometry, redshifts, and spectral data

Abstract

We present a preliminary data release from our multi-year campaign at Keck Observatory to study the host galaxies of a large sample of Swift-era gamma-ray bursts via multi-color ground-based optical imaging and spectroscopy. With over 160 targets observed to date (and almost 100 host detections, most of which have not previously been reported in the literature) our effort represents the broadest GRB host survey to date. While targeting was heterogeneous, our observations span the known diversity of GRBs including short bursts, long bursts, spectrally soft GRBs (XRFs), ultra-energetic GRBs, X-ray faint GRBs, dark GRBs, SN-GRBs, and other sub-classes. We also present a preview of our database (currently available online via a convenient web interface) including a catalog of multi-color photometry, redshifts and line ID's. Final photometry and reduced imaging and spectra will be available in the near future.