[vsnet-grb-info 13904] GRB 130912A: Skynet DSO-14/Yerkes-41/PROMPT-CTIO observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15218
SUBJECT: GRB 130912A: Skynet DSO-14/Yerkes-41/PROMPT-CTIO observations
DATE:    13/09/12 17:07:49 GMT
FROM:    Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet  <atrotter at physics.unc.edu>

A. Trotter, D. Reichart, J. Haislip, A. LaCluyze, A. B. Smith, D. Caton, 
L. Hawkins, V. Hoette, K. Cudworth, D. Harper, R. Kron, T. Linder, R. 
Russell, E. Struble, T. Berger, H. T. Cromartie, R. Egger, A. Foster, N. 
Frank, K. Ivarsen, M. Maples, J. Moore, M. Nysewander, and J. A. Crain 
report:

Skynet observed the Swift/XRT localization of GRB 130912A (D'Elia et 
al., GCN 15212, Swift trigger 570465) with the 14" telescope at the 
Appalachian State University Dark Sky Observatory (DSO-14) in NC, USA (R 
and I bands), the 41" telescope of Yerkes Observatory in WI, USA (r' and 
i' bands), and with four 16" telescopes of the PROMPT array at CTIO, 
Chile (B, V, R, and I bands).

Starting at 2013-09-12, 08:47 UT and continuing until 10:26 UT 
(t=12m-111m post-trigger), Skynet took a total of 72 160s exposures. In 
stacked images, we do not detect an optical source in any band in or 
near the XRT error circle.  Our 3-sigma limiting magnitudes are 
tabulated below:

==================================
tmid  scope   expos  fil  limit
==================================
21m  DSO-14   2x160s  I  >18.7
24m  DSO-14   2x160s  R  >19.6
61m  Prompt5 10x160s  I  >20.6
61m  Prompt4 10x160s  R  >21.0
61m  Prompt1 10x160s  V  >21.3
61m  Prompt3 10x160s  B  >21.1
63m  Y-41    11x160s  i' >21.6
60m  Y-41     9x160s  r' >21.9
66m  Y-41     8x160s  g' >21.8
==================================

BVRI magnitudes are in the Vega System, and g'r'i' magnitudes are in the 
AB system, calibrated to 4 APASS stars in the field.  Magnitudes have 
not been corrected for line-of-sight Milky Way dust extinction, with 
expected E(B-V)=0.28 (Schlegel et al. 1998).

No further Skynet observations are scheduled.