[AAVSO-HEN] GRB080604: HET redshift retraction

[grb at aavso.org]

The following is a GCN Circular circulated via the AAVSO network.
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TITLE:   GCN CIRCULAR
NUMBER:  7819
SUBJECT: GRB080604: HET redshift retraction
DATE:    08/06/04 20:56:18 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara at astro.psu.edu>

A. Cucchiara and D. B. Fox  (Penn State) report:

Based on updated calibration files we re-analyzed the GRB080604 spectrum
taken at HET (GCN 7805). The features reported in the previous GCN are no
longer significant at a 3-sigma confidence level.
Furthermore, only an upper limit of z < 2.8 can be derived from our dataset.

Our revised results are consistent with the results from Gemini-North 
spectroscopy
(Wiersama et al., GCN 7818).  The low signal to noise of our spectrum 
does not
permit detection of the absorption features associated with the z=1.416 
system
seen in those data.