Difference: GCNCIRCULAR21544 ( vs. 1)

N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick) report on behalf of the VINROUGE collaboration.

We observed the region around the location of the proposed optical counterpart of LIGO/Virgo G298048 (Coulter et al. LVC GCN 21529) using the VIRCAM camera on the wide-field ESO VISTA telescope. The source is clearly detected with a provisional magnitude J(AB)=17.5+/-0.1 at Aug-18 00:10 UT. We note that this is consistent with colours that are flat in Fnu, as noted by Nicholl et al. (LVC GCN 21541) from DECam data taken at a similar epoch. Further analysis is ongoing.

We thank the staff at Paranal for their excellent support of these observations.

-- ThomasKupfer - 18 Aug 2017