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 17747

GRB 150423A: WHT observations
2015-04-24T11:35:37Z (9 years ago)
Klaas Wiersema at U Leicester <>
K. Wiersema (Leicester), A. Levan (Warwick), N. Tanvir (Leicester), C. MacLeod
(IfA Edinburgh), F. Riddick (ING) report:

We observed the position of GRB 150423A (Pagani et al. GCN 17728) using the
ACAM instrument on the William Herschel Telescope, at La Palma. We obtained
images with 5 x 300 sec exposure time in both sloan g and z bands, starting at 
22:30 UT on 23 April 2015. The nearby galaxy (Varela et al. GCN 17732; Perley et
al. GCN 17744) is clearly detected, but the afterglow (Varela et al. GCN 17732)
is not significantly detected, with a 5 sigma limit of g~25.3 (calibrated using
SDSS field objects). A low significance object may be present near the afterglow
position in g band, as well as some faint galaxies, which may be candidate hosts.
See here for an image of the field:
Looking for U.S. government information and services? Visit