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GCN Circular 1582

GRB 021004: Optical observations
2002-10-05T16:38:36Z (22 years ago)
T.P. Prabhu at Indian Astro. Obs. <>
G.C. Anupama, D.K. Sahu, B.C. Bhatt and T.P. Prabhu, (Indian Institute of
Astrophysics, Bangalore) report on behalf of a larger collaboration
optical observations of GRB 021004 obtained from the 2-m Himalayan Chandra
Telescope, Indian Astronomical Observatory, Hanle:

We have monitored GRB 021004 in BVRI bands and obtained spectra with a
resolution of 1.8 nm on 2002 October 4. The spectrum in the range of
500-1000 nm at October 4.883 UT shows z=1.38 and 1.60 reported in GCN
#1569 and also indicates a higher redshift of z=1.72. The absorption-lines
identified are:

Obs (A)	ident (A)	z

5576	FeII 2343	1.38
6093	FeII 2343	1.60
6166	FeII 2586	1.38
6654	MgII 2796	1.38
6669	MgII 2803	1.38
6757	FeII 2599	1.60
7269	MgII 2796	1.60
7296	MgII 2803	1.60
7601	MgII 2796	1.72
7629	MgII 2803	1.72

Assuming the USNO star has R=15.64, the R magnitudes at the beginning and
end of observing run were:

2002 October 4.70 UT	R=17.44
	     4.95 UT	R=18.59

[GCN OPS NOTE (05oct02):  This submission was received at 13:52 05 Oct 02 UT,
but was delayed in distribution due to the lack of an entry in the vetting
list.  A new entry was added and the submission manually invoked.]
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