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 10294

Subject
GRB 091221: Skynet/PROMPT Detections
Date
2009-12-23T22:11:00Z (14 years ago)
From
Josh Haislip at U.North Carolina <haislip@physics.unc.edu>
J. Haislip, D. Reichart, K. Ivarsen, A. LaCluyze, R. Egger, A. Foster, J. 
Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. 
Nysewander report:

Skynet observed the Swift/BAT localization of GRB 091221 (Palmer et al., 
GCN 10283) with four of the 16" PROMPT telescopes at CTIO beginning 4.3 
hours after the trigger in BVRI.

We detect the afterglow (Palmer et al., GCN 10283; Zheng et al., GCN 
10284).  Stacking only images that increase the limiting magnitude yields:

mean                                                       1-sig. 1-sig.
time                                                       sys.   stat.
since                                          cal.        cal.   cal.
trig. tel.     exp.     fil. magnitude         stars       unc.   unc.
(h)            (# x s)                                     (mag)  (mag)

4.9   PROMPT-5 44 x 80  I    > 21.1 (3 sigma)  143 USNO B1 0.338  0.000
            + 1 x 40
4.9   PROMPT-4 42 x 80  R    21.49 +0.27 -0.22 139 USNO B1 0.362  0.000
4.9   PROMPT-3 41 x 80  B    > 21.5 (3 sigma)  82 USNO B1  0.154  0.000
4.9   PROMPT-1 41 x 80  V    21.41 +0.42 -0.31 27 NOMAD    0.193  0.000
7.3   PROMPT-3 136 x 80 B    > 22.1 (3 sigma)  79 USNO B1  0.153  0.000
7.3   PROMPT-5 134 x 80 I    > 21.8 (3 sigma)  120 USNO B1 0.337  0.000
7.3   PROMPT-4 139 x 80 R    22.44 +0.38 -0.28 112 USNO B1 0.392  0.000
7.4   PROMPT-1 145 x 80 V    > 22.0 (3 sigma)  28 NOMAD    0.112  0.000
Looking for U.S. government information and services? Visit USA.gov