GCN Circular 6458
Subject
GRB 070518: optical observation
Date
2007-05-23T15:53:05Z (17 years ago)
From
Giuseppe Greco at U Bologna <giuseppe.greco2@studio.unibo.it>
F. Terra (Second University of Roma "Tor Vergata"), G. Greco, C. Bartolini,
A. Guarnieri, A. Piccioni (Bologna University), G. Pizzichini (INAF/IASF
Bologna), D. Nanni (INAF/OAR and Second University of Rome "Tor Vergata"),
S. Karpov (Special Astrophysical Observatory, Russia),
S. Galetti and R. Gualandi (Bologna Observatory) report:
During the night of 07/05/18 we observed the OT of GRB070518
(Guidorzi et al., GCN 6415) with the 1.52 cm telescope
of the Bologna Observatory in Loiano under moderate
sky conditions (seeing ~ 2").
The OT flux was slightly blended with a nearby star (R ~ 18.7).
To correct for the blending we employed difference image analysis techniques.
By adding two consecutive 30 min exposures in the Rc filter at
mean time 23.5 UT we find Rc = 22.3 +/- 0.2 based on the USNO-A2.0 catalog.
Our coadded image have been posted in our public directory
from where they can be retrieved by sftp using
hostname: ermione.bo.astro.it
username: publicGRB
password: GRB_bo.