GCN Circular 395
Subject
GRB 990806, Optical Observations
Date
1999-08-07T23:03:52Z (25 years ago)
From
Jonathan Kemp at Biosphere2 Center & Columbia U <jonathan@astro.bio2.edu>
J. Kemp, N. Mirabal, J. Halpern (Columbia), J. Parker (SwRI),
D. Harkavy (Harvard), E. Costa, & L. Piro (IAS/CNR, Frascati)
report on behalf of the BeppoSAX team and the MDM Observatory
GRB follow-up team's southern extension:
"We imaged the BeppoSAX WFC error circle of GRB 990806 (Piro GCN 392)
starting on Aug. 7.19 UT using the CTIO 4m and 0.9m telescopes.
In a 5 minute V-band exposure on the 4m, no new object brighter
than the limit of the various sky survey plates is seen. The same
is true of a series of ten 10 minute R-band images obtained on the
0.9m between Aug. 7.21 and 7.42 UT. No variable object is seen.
The 5-sigma limiting magnitude of the summed R-band image is 23.0.
Photometric calibration was obtained using the Landolt standard
field of PG 2213-006. For possible future reference, we give
recalibrated magnitudes of several stars from the USNO-A2.0 catalog:
Star RA(2000) Dec(2000) R(USNO) R(CTIO)
-----------------------------------------------------
A 03 10 19.577 -68 09 52.08 16.7 16.83
B 03 10 21.996 -68 05 31.11 16.1 16.09
C 03 10 32.916 -68 04 17.54 16.8 17.07
D 03 10 37.871 -68 07 44.91 17.0 17.15
E 03 10 41.537 -68 06 19.68 16.6 16.50
F 03 10 52.539 -68 06 30.05 15.7 15.58
G 03 10 57.979 -68 05 01.92 16.2 16.33
-----------------------------------------------------
A finding chart for these stars and a CCD image are posted at
http://www.astro.bio2.edu/grb/
This message may be cited."
[GCN OPS NOTE (07Aug99): There was a typo in the original URL.
The URL in this archive copy of the Circular has been corrected
at the author's request.]