[vsnet-grb-info 4382] GRB 060605 new redshift

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6166
SUBJECT: GRB 060605 new redshift
DATE:    07/03/02 10:53:40 GMT
FROM:    Patrizia Ferrero at TLS Tautenburg  <ferrero at tls-tautenburg.de>

S. Savaglio, MPE Garching,  E. Palazzi, INAF-IASF, Bologna,
P. Ferrero & S. Klose, TLS Tautenburg, report:


We have re-analyzed the spectrum of GRB 060605 afterglow taken with  
the Integral Field Unit PMAS/PPak (Ferrero et al. 2006, GCN 5489). We  
found a new strong SiIV absorption system with Ly-alpha, at redshift  
z=3.78. This redshift is higher than the previous claimed redshift of  
the GRB, z=3.711 (Ferrero et al. 2006, GCN 5489), which also show  
SiIV absorption. These two SiIV  absorptions are separated by about  
4000 km/s, and are similar to the double CIV absorption detected in  
the afterglow of GRB 021004 (separation 2400 km/s; Savaglio et al.  
2002, GCN 1633; Fiore et al. 2005, 624, 853) and GRB 030226  
(separation 2400 km/s; Klose et al. 2004, AJ 128, 1942).
A redshift z=3.8 for GRB 060605 was previously suggested by Peterson  
et al. (GCN 5223).

This message may be quoted.