[AAVSO-HEN] GRB 060204b: pseudo-z from spectral parameters of the prompt emission

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4704
SUBJECT: GRB 060204b: pseudo-z from spectral parameters of the prompt emission
DATE:    06/02/07 14:21:22 GMT
FROM:    Jean-Luc Atteia at Lab d Astrophys.,OMP,Toulouse  <atteia at ast.obs-mip.fr>

A. Pelangeon & J-L. Atteia (LATT-OMP) report:

We have used the spectral parameters for the most intense part of GRB
060204B (from T0-4.46 sec. to T0+10.54 sec.) kindly provided by T. Sakamoto
(GSFC, private communication) to compute the spectral pseudo-redshift of
this burst detected by SWIFT-BAT (Falcone et al., GCN 4655; Markwardt et
al., GCN 4671).

We find a pseudo-redshift pz= 3.1 ± 1.1

This is consistent with the observations of the afterglow by Fynbo et al.
(GCN 4677) who imposes a conservative maximum redshift of z ~< 4.