GCN Circular 22995
Subject
GRB 180721A: LCO Haleakala observations
Date
2018-07-21T13:28:40Z (6 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi, R. Martone (U. Ferrara), S. Kobayashi (LJMU), C.G. Mundell
(U. Bath), A. Gomboc (U. Nova Gorica), I.A. Steele (LJMU), A. Cucchiara,
D. Morris (U. of Virgin Islands) on behalf of a large collaboration report:
The LCO 2-m unit at Haleakala Observatory (Hawaii) automatically began
observing Swift GRB 180721A (Sbarufatti et al. GCN 22994) on July 21,
11:21:40 UT (14.9 minutes after the GRB trigger time) with the SDSS i'
filter. Within the Swift-XRT error circle we do not detect any source
down to i'>20.2 mag at a mid time of 20.4 minutes post GRB with a 5x120s
exposure, as calibrated against nearby SDSS objects.