Program: GN-2017A-Q-23

We have entered a new era of non-electromagnetic astronomy. First, gravitational wave astronomy is now a reality with two high quality Black-Hole/Black-Hole merger events recently discovered by the Advanced Laser Interfermetric Gravitational Wave Observeratory or LIGO (Abbott et al, 2016a, 2016b). The increase in sensitivity of this experiment by more than an order of magnitude has now opened up the prospect of routine discovery of gravitational wave sources. The aLIGO/Virgo detector favours transient sources (neutron star or black hole mergers, and massive asymmetric core-collapse supernovae), with sky localisation regions of 100s to a 1000 square degrees. Second, after years of detecting ultra-high energy neutrinos and establishing their cosmic background, through post-processing of accumulated data, the IceCube 1 kilometer detector array in Antartica (Aartsen Collaboration 2013, 2015) has released two real time neutrino events with localizations of a square degree or so (GCN 19363, IceCube 160731) Our team now leads the world (Smartt, Chambers et al 2016a, Smartt, Chambers et al 2016b, Abbott et al., 2016c) in the search for optical counterparts to these events because of (a) the Pan-STARRS suvey capability, (b) our pre-existing images of the sky from the 3pi Steradian Survey, (c) our extensive software infrastructruce for image subtraction and machine learning to sort thousands of candidates, and (d) our access to Target of Opportunity Time on Mauna Kea. Having proved our capability to respond rapidly , this proposal is to continue our program of searching for the counterparts to both gravitational wave and ultra-high energy neutrino events