[vsnet-grb-info 3357] GRB060526, optical observations

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5192
SUBJECT: GRB060526,  optical observations
DATE:    06/05/31 18:48:03 GMT
FROM:    Adalberto Piccioni at Astronomy, Bologna U.  <adb at piccio.org>

F. Terra (Second University of Roma "Tor Vergata"), G. Greco,
C. Bartolini, A. Guarnieri, A. Piccioni (Bologna University),
D. Nanni (INAF/OAR and Second University of Roma "Tor Vergata"),
I. Bruni, S. Galleti (Bologna Observatory) and G. Pizzichini
(INAF/IASF Bologna) report:

"We observed the field of GRB 060526 (Campana et. al., GCN 5162)
with the 152 cm Cassini Telescope located in Loiano, equipped
with BFOSC in the nights april 26-27 (seeing 2".0) and 27-28
(seeing 1".7).
The photometry is based on the SDSS stars (Cool et al. GCN 5164)
and trasformation derived from Lupton (2005). Using this
transformation we find for the USNO B-1 star (RA = 15 31 18.6,
DE = +00 17 34.9) the magnitude Rc = 16.50, consistent with the 
calibration of Khamitov et al. (GCN 5177).

We find the following magnitudes:

Mean...UT .......Filter........Exptime (s).......magnitude
May...26.908........Rc............900............18.85+/-0.08
May...26.921........Rc............900............18.92+/-0.07
May...26.935........V............1200............19.37+/-0.08
May...26.949........I.............900............18.60+/-0.06
May...26.961........Rc............900............19.08+/-0.07
May...26.975........V............1200............19.64+/-0.09
May...26.990........I.............900............18.80+/-0.06
May...27.002........Rc............900............19.28+/-0.09
May...27.017........V............1200............19.79+/-0.11
May...27.031........I.............900............18.94+/-0.08
May...28.002........Rc............900............20.61+/-0.13
May...28.017........Rc............900............20.44+/-0.10