Iron line afterglows: How to produce them

¹ Osservatorio Astronomico di Brera, Via Bianchi 46, I–23807 Merate (Lc), Italy
² Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I–20133 Milano, Italy

Received: 29 December 1998
Accepted: 9 June 1999

Abstract

We discuss how a powerful iron line emission can be produced if iron rich solar masses are concentrated in the close vicinity of the burst. Recombination, thermal and fluorescent reflection are discussed. We find that recombination suffers the high Compton temperature of the plasma while the other two scenarios are not mutually exclusive and could account for the claimed iron line detected in two afterglows.