Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to https://gcn.nasa.gov.
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

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.]
Looking for U.S. government information and services? Visit USA.gov