DECAM-GROWTH SEARCH FOR THE FAINT AND DISTANT BINARY NEUTRON STAR AND NEUTRON STAR-BLACK HOLE MERGERS IN O3A

Synoptic searches for the optical counterpart to a binary neutron star (BNS) or star-black hole (NSBH) merger can pose significant challenges towards discovery of kilonovae and performing multi-messenger science. In this work, we describe advantage global multi-telescope network end, with particular focus on key complementary role Dark Energy Camera (DECam) plays in multi-facility follow-up. We Global Relay Observatories Watching Transients Happen (GROWTH) Target-of-Opportunity (ToO) Marshal, common web application built ingest events, plan observations, search transient candidates, retrieve performance summary statistics all telescopes our network. Our infrastructure enabled us conduct observations two events during O3a, S190426c S190510g. Furthermore, analysis deep DECam S190814bv conducted by DESGW team, access variety follow-up facilities allowed place meaningful constraints parameters kilonova merging binary. emphasize importance telescope conjunction power like counterparts gravitational-wave sources.