LIGO/Virgo G298048: Observation of the potential optical counterpart in NGC 4993

We imaged SSS17a in NGC 4993 (Coutler et al. LVC GCNs 21529), the potential optical counterpart of LIGO/Virgo G298048 (LVC GCNs 210505, 21509, 21513) with the g, r, i, z and an array of medium-band filters. The observation was carried out using two 0.43m telescopes, LSGT and T17 of iTelescope.Net at the Siding Spring Observatory (Im et al. 2015, JKAS, 48, 207). The observation started at 2017-08-18 09:47 (UT), and continued for about 30 min until the weather stopped the osbservation. SSS17a is clearly visible in the images taken. Further analysis of the data is ongoing. Additional observations are ongoing/planned using these telescopes and the KMTNet 1.5m telescopes in the coming nights.