Detailed Afterglow Modeling and Host Galaxy Properties of the Dark GRB 111215A

Abstract

Gamma-ray burst (GRB) 111215A was bright at X-ray and radio frequencies, but not detected in the optical or near-infrared (nIR) down to deep limits. We have observed the GRB afterglow with the Westerbork Synthesis Radio Telescope and Arcminute Microkelvin Imager at radio frequencies, with the William Herschel Telescope and Nordic Optical Telescope in the nIR/optical, and with the Chandra X-ray Observatory. We have combined our data with the Swift X-Ray Telescope monitoring, and radio and millimeter observations from the literature to perform broadband modeling, and determined the macro- and microphysical parameters of the GRB blast wave. By combining the broadband modeling results with our nIR upper limits we have put constraints on the extinction in the host galaxy. This is consistent with the optical extinction we have derived from the excess X-ray absorption, and higher than in other dark bursts for which similar modeling work has been performed. We also present deep imaging of the host galaxy with the Keck I telescope, Spitzer Space Telescope, and Hubble Space Telescope (HST), which resulted in a well-constrained photometric redshift, giving credence to the tentative spectroscopic redshift we obtained with the Keck II telescope, and estimates for the stellar mass and star formation rate of the host. Finally, our high resolution HST images of the host galaxy show that the GRB afterglow position is offset from the brightest regions of the host galaxy, in contrast to studies of optically bright GRBs.

11 pages, 4 figures, 4 tables; accepted for publication in MNRAS

References in corpus (5)

• Long gamma-ray bursts and core-collapse supernovae have different environments
• Swift Identification of Dark Gamma-Ray Bursts
• The optically unbiased GRB host (TOUGH) survey. I. Survey design and catalogs
• GRB 130925A: an ultra-long Gamma Ray Burst with a dust-echo afterglow, and implications for the origin of the ultra-long GRBs
• The dark nature of GRB 051022 and its host galaxy

Cited by in corpus (12)

• A Comparative Study of Long and Short GRBs. I. Overlapping Properties
• The Arcminute Microkelvin Imager Catalogue of Gamma-ray Burst afterglows at 15.7 GHz
• Are the host galaxies of Long Gamma-Ray Bursts more compact than star-forming galaxies of the field?
• Constraints on Electron Acceleration in Gamma-Ray Bursts Afterglows from Radio Peaks
• Chandra and Hubble Space Telescope observations of dark gamma-ray bursts and their host galaxies
• Detailed multi-wavelength modelling of the dark GRB 140713A and its host galaxy
• Radio data challenge the broadband modelling of GRB160131A afterglow
• Rapid-response radio observations of short GRB 181123B with the Australia Telescope Compact Array
• Rapid radio brightening of GRB 210702A
• The Case for a High-Redshift Origin of GRB100205A
• Diagnosing Circumburst Environment with Multiband Gamma-Ray Burst Radio Afterglows
• A Radio-selected Population of Dark, Long Gamma-ray Bursts: Comparison to the Long Gamma-ray Burst Population and Implications for Host Dust Distributions