The signature of the central engine in the weakest relativistic explosions: GRB 100316D

R. Margutti, A. M. Soderberg, M. H. Wieringa, P. G. Edwards, R. A. Chevalier, B. J. Morsony, Rodolfo Barniol Duran, L. Sironi, B. A. Zauderer, D. Milisavljevic, A. Kamble, E. Pian

Research output: Contribution to journalArticlepeer-review

51 Scopus citations

Abstract

We present late-time radio and X-ray observations of the nearby sub-energetic gamma-ray burst (GRB)100316D associated with supernova (SN) 2010bh. Our broad-band analysis constrains the explosion properties of GRB 100316D to be intermediate between highly relativistic, collimated GRBs and the spherical, ordinary hydrogen-stripped SNe. We find that ∼1049erg is coupled to mildly relativistic (Γ = 1.5-2), quasi-spherical ejecta, expanding into a medium previously shaped by the progenitor mass-loss with a rate of (for an assumed wind density profile and wind velocity vw= 1000 km s-1). The kinetic energy profile of the ejecta argues for the presence of a central engine and identifies GRB 100316D as one of the weakest central-engine-driven explosions detected to date. Emission from the central engine is responsible for an excess of soft X-ray radiation that dominates over the standard afterglow at late times (t > 10 days). We connect this phenomenology with the birth of the most rapidly rotating magnetars. Alternatively, accretion onto a newly formed black hole might explain the excess of radiation. However, significant departure from the standard fall-back scenario is required.

Original languageEnglish (US)
Article number18
JournalAstrophysical Journal
Volume778
Issue number1
DOIs
StatePublished - Nov 20 2013

Keywords

  • gamma-ray burst: general
  • gamma-ray burst: individual (GRB 100316D)

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint

Dive into the research topics of 'The signature of the central engine in the weakest relativistic explosions: GRB 100316D'. Together they form a unique fingerprint.

Cite this