XRF 050406 late-time flattening: an inverse Compton component?

¹ IASF-Roma/INAF, Via Fosso del Cavaliere 100, 00133 Roma, Italy e-mail: Alessandra.Corsi@iasf-roma.inaf.it
² Università degli studi di Roma “La Sapienza”, Piazzale Aldo Moro 5, 00185 Roma, Italy
³ INFN – Sezione di Roma c/o Dip. di Fisica – Università degli studi di Roma “La Sapienza”, Piazzale Aldo Moro 5, 00185 Roma, Italy

Received: 27 March 2006
Accepted: 19 July 2006

Abstract

Aims.We investigate for possible evidence of inverse Compton (IC) emission in the X-ray afterglow of XRF 050406.

Methods.In the framework of the standard fireball model, we show how the late-time flattening observed in the X-ray light curve between ~10⁴ s and ~10⁶ s can be explained in a synchrotron-plus-IC scenario when the IC peak frequency crosses the X-ray band.

Results.We thus conclude that the appearance of an IC component above the synchrotron one at late times successfully accounts for these X-ray observations.