Late-time observations of GRB 080319B: jet break, host galaxy, and accompanying supernova

Nial R Tanvir, Evert Rol, Andrew J Levan, Karl Mikael Svensson, Andrew S Fruchter, Jonathan Granot, Paul T O'Brien, Klass Wiersema, Rhaana L C Starling, Pall Jakobsson, Johan Peter Uldall Fynbo, Jens Hjorth, Peter A Curran, Alexander J van der Horst, Chryssa Kouveliotou, Judith Lea Racusin, David N Burrows, Franck Genet

Research output: Contribution to journalArticleResearchpeer-review

32 Citations (Scopus)

Abstract

The Swift-discovered GRB 080319B was by far the most distant source ever observed at naked-eye brightness, reaching a peak apparent magnitude of 5.3 at a redshift of z = 0.937. We present our late-time optical (Hubble Space Telescope, Gemini, and Very Large Telescope) and X-ray (Chandra) observations, which confirm that an achromatic break occurred in the power-law afterglow light curve at 11 days post-burst. This most likely indicates that the gamma-ray burst (GRB) outflow was collimated, which or a uniform jet would imply a total energy in the jet Ejet less than or equal to 1052 erg. Our observations also show a late-time excess of red light, which is well explained if the GRB was accompanied by a supernova (SN), similar to those seen in some other long-duration GRBs. The latest observations are dominated by light from the host and show that the GRB took place in a faint dwarf galaxy (r(AB) approx equal to 27.0, rest frame MB approx equal to -17.2). This galaxy is small even by the standards of other GRB hosts, which is suggestive of a low-metallicity environment. Intriguingly, the properties of this extreme event-a small host and bright SN-are entirely typical of the very low luminosity bursts such as GRB 980425 and GRB 060218
Original languageEnglish
Pages (from-to)625 - 632
Number of pages8
JournalThe Astrophysical Journal
Volume725
Issue number1
DOIs
Publication statusPublished - 2010
Externally publishedYes

Cite this