TITLE:   GCN CIRCULAR
NUMBER:  6218
SUBJECT: Short-Hard GRB 070209: PROMPT Observations
DATE:    07/03/19 22:10:03 GMT
FROM:    Seth Johnson at U.North Carolina  <spjohnso@physics.unc.edu>

S. Johnson, D. Reichart, J. Haislip, M. Nysewander, A. LaCluyze, K.
Ivarsen, J. A. Crain, A. Foster and A. Trotter report on behalf of the
University of North Carolina:

Skynet observed the localization of short-hard GRB 070209 (Sato et al., GCN
6086) with one of the 16" PROMPT telescopes at CTIO beginning 67 seconds
after the burst in BVIR.

Our images include nearly all of the BAT error circle, as well as all three
X-ray sources of Stratta et al. (GCN 6095).  No new source is detected
within this region to the following 3-sigma limiting magnitudes:

Filter  Mean Time       Integration     Limiting        Calibration
        Since GRB       Time (sec)      Magnitude       Stars*

B       0:01:12         10              16.07           1-3
V       0:01:39         10              16.83           1-4,7
R       0:02:11         20              17.33           9-12
I       0:02:49         20              17.24           9-12
B       0:03:27         10              16.27           1-4
V       0:04:11         40              18.08           1-6
R       0:05:16         40              17.94           9-14
I       0:06:13         40              17.68           9-12,15
B       0:07:35         80              18.17           1-6
V       0:09:14         80              18.57           1-6
R       0:10:57         80              18.62           9-15
I       0:12:36         80              18.26           9-14
B       0:14:44         120             18.82           1-6
V       0:17:28         120             19.12           1-6
R       0:20:14         120             18.81           9-14
I       0:23:00         120             18.66           9-15
B       0:25:43         120             18.41           1-6
V       0:29:33         240             19.36           1-6
R       0:34:34         240             19.19           9-14,16
I       0:40:19         240             18.64           9-14,16
B       0:45:45         240             18.41           1-6
V       0:51:06         240             19.37           1-2,4-6
R       0:58:55         560             19.77           9-10,12-14,16
I       1:10:51         560             19.32           9-10,12-14,16
B       1:21:29         480             19.09           1-2,4-7
V       1:33:25         560             19.72           1-2,4-8

*We calibrated the field in B and V using stars from the NOMAD catalog and
in R and I using stars from the USNO-B1.0 catalog.  The NOMAD calibration
stars are (1) 0426-0037919, (2) 0426-0037965, (3) 0425-0038295, (4)
0425-0038481, (5) 0425-0038222, (6) 0426-0037846, (7) 0427-0037455 and (8)
0426-0038099.  The USNO-B1.0 calibrations stars are (9) 0426-0037895, (10)
0426-0037941, (11) 0425-0038287, (12) 0425-0038472, (13) 0425-0038213, (14)
0426-0037820, (15) 8058-00193-1 and (16) 0426-0038075.