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

GCN Circular 14427

Skynet/GORT observations of GRB130420A
2013-04-20T22:28:05Z (11 years ago)
Adam S. Trotter at UNC-Chapel Hill/NC AnTPROMPT/Skynet <>
A. Trotter, N. Frank, A. LaCluyze, D. Reichart, K. McLin,  L. Cominsky,
T. Berger, J. A. Crain, H. T. Cromartie,  R. Egger, A. Foster, J.
Haislip, K. Ivarsen, M. Maples, J. Moore,   M. Nysewander, and E.
Speckhard report:

Skynet observed the Swift/BAT localization of GRB 130420A (Page et al.,
GCN 14406, Swift trigger 553977) with the 14" GLAST Optical Robotic
Telescope (GORT) at the Hume observatory in California, beginning ~100s
after the trigger in RcIc, and continuing until the source set at
t=4.9h. We detect the afterglow reported by Guidorzi et al. (GCN 14405)
at RA 13:04:06.6, Dec +59:25:25.2 (J2000), within the error circle
reported by the Swift XRT (GCN 14406). Photometry was calibrated to six
SDSS stars in the field.
The afterglow exhibits a rising light curve in both Rc and Ic bands at
early times, peaking at t=330s (peak Rc~16, Ic~15.5), after which it
fades with an approximate temporal index alpha~-1.  There is some
evidence for flattening of the Ic-band light curve at t>1h, at which
time Ic~18.7.

Follow-up observations at GORT have been scheduled.

A preliminary light curve of the first night's data can be found at:
Looking for U.S. government information and services? Visit