Korea Microlensing Telescope Network    

Follow-up observations of GW170817

2017-10-19 / PM 01:10:18

Three KMTNet 1.6-m telescopes performed follow-up observations of the optical counterpart of the gravitational wave transient GW170817. This transient was discovered by Advanced LIGO and Virgo collaboration on 17 August 2017 at 12:41 UT and turned out to be originated from the merger of two neutron stars. We monitored the optical counterpart in the early type galaxy NGC4993 for about 3 weeks starting from 18 August 2017. Our multi-band BVRI photometric data were used for investigating the radioactive glow (so-called kilonova) caused by colliding two neutron stars. The results were published at two journals of Nature and ApJ Letters.

Optical counterpart of GW170817 taken with the KMTNet-SAAO system(right object of the solid line). The bright galaxy NGC4993 is shown near the center.
Light curves of GW170817 in optical and infrared passbands (from Troja et al. 2017, Nature, 551, 71). Most of BVRI data (bluish filled circles) from 1.2 to 8.0 days were obtained from the KMTNet system.