The variable X-ray light curve of GRB 050713A: the case of refreshed shocks

Abstract

We present a detailed study of the spectral and temporal properties of the X-ray and optical emission of GRB050713a up to 0.5 day after the main GRB event. The X-ray light curve exhibits large amplitude variations with several rebrightenings superposed on the underlying three-segment broken powerlaw that is often seen in Swift GRBs. Our time-resolved spectral analysis supports the interpretation of a long-lived central engine, with rebrightenings consistent with energy injection in refreshed shocks as slower shells generated in the central engine prompt phase catch up with the afterglow shock at later times. Our sparsely-sampled light curve of the optical afterglow can be fitted with a single power law without large flares. The optical decay index appears flatter than the X-ray one, especially at later times.

few changes, to be published in A&A

Cited by in corpus (12)

• The First Survey of X-ray Flares from Gamma Ray Bursts Observed by Swift: Temporal Properties and Morphology
• The Host Galaxies of Swift Dark Gamma-Ray Bursts: Observational Constraints on Highly Obscured and Very High-Redshift GRBs
• High Energy Afterglow from Gamma-ray Bursts
• MAGIC upper limits on the very high energy emission from GRBs
• The Early-time Optical Properties of Gamma-Ray Burst Afterglows
• The complex light-curve of the afterglow of GRB071010A
• Swift and Fermi observations of X-ray flares: the case of Late Internal Shock
• High energy afterglows and flares from Gamma-Ray Burst by Inverse Compton emission
• An Estimation of the Gamma-Ray Burst Afterglow Apparent Optical Brightness Distribution Function
• A detailed radio study of the energetic, nearby and puzzling GRB 171010A
• The exceptionally extended flaring activity in the X-ray afterglow of GRB 050730 observed with Swift and XMM-Newton
• Gamma-Ray Burst high energy emission from Internal Shocks