TITLE:   GCN CIRCULAR
NUMBER:  21745
SUBJECT: LIGO/Virgo G299232: GRAWITA Asiago/Copernico Telescope observations
DATE:    17/08/29 10:29:47 GMT
FROM:    Stefano Benetti at INAF-OAPd  <stefano.benetti@oapd.inaf.it>

L. Tomasella, S. Benetti, E. Cappellaro (INAF-OAPD), L. Amati (INAF-IASF Bo), L. A. Antonelli, S. Ascenzi (INAF-OAR),  M.T. Botticella (INAF-OAC), M. Branchesi (GSSI), S. Campana, S. Covino, P. D'Avanzo (INAF-OAB), V. D'Elia (INAF-ASDC), D. Fugazza, F. Getman, A. Grado (INAF-OAC), G. Greco (Urbino University/INFN Firenze), L. Limatola (INAF-OAC), M. Lisi (INAF-OAR), A. Melandri (INAF-OAB), L. Nicastro, E. Palazzi, E. Pian (INAF-IASF Bo), S. Piranomonte, L. Pulone (INAF-OAR), A. Rossi (INAF-IASF Bo), P. Schipani (INAF-OAC), G. Stratta (Urbino University/INFN Firenze), G. Tagliaferri (INAF-OAB), V. Testa (INAF-OAR), S. Yang (INAF-OAPD), E. Brocato (INAF-OAR) on behalf of GRavitational Wave Inaf TeAm report:

We observed the field of the Optical Transient Discovery by Swift/UVOT (LVG GCN 21733) with the Asiago 1.82 m Copernico Telescope equipped with AFOSC under poor sky conditions. We do not detected the Swift OT down to the following limits:

Filter (SDSS)  average UT  total Exp (s)  limit (ABmag)
u            20170828.90    1800    22.5
g            20170828.89      270    21.6
r            20170828.88      270    20.8
i            20170828.93      270    21.9
z            20170828.92      900    21.4

We note the presence of the galaxy UGC 1178 at about 5 arcmin from the position of the OT. This galaxy has a redshift z=0.018399, and the projected distance of the OT seen by UVOT would then correspond to about 120 Kpc from the galaxy center.

[GCN OPS NOTE(29aug17):  Per author's request, The Subject-line was changed from "...INAF Asiago/Copernico..."
to "...GRAWITA Asiago/Copernico...". And the the last paragraph "UGC 1178a" was changed to "UGC 1178".