TITLE: GCN CIRCULAR NUMBER: 26476 SUBJECT: LIGO/Virgo S191216ap: galaxies consistent with GW + Neutrino + HAWC position DATE: 19/12/17 16:19:32 GMT FROM: Varun Bhalerao at Indian Inst of Tech H. Kumar (IITB), A. Sagués Carracedo (OKC, Stockholm University), T. Ahumada (UMD), I. Andreoni (Caltech), V. Bhalerao (IITB) report on behalf of the GROWTH collaboration: We cross-matched the HAWC trigger position (HAWC Collaboration, GCN 26472) with the GLADE catalog (Dalya et al., 2018), to identify sources within 0.9 degrees (approximately 3-sigma) of the HAWC position RA, Dec = 323.53, 5.23. We further applied a distance constraint based on the 3D Bayestar localisation provided by the LVC (bayestar.fits.gz,1), using mean distance = 95.6 Mpc and distance sigma = 37.4 Mpc, appropriate for this direction. We find four objects in GLADE 1 (http://vizier.u-strasbg.fr/viz-bin/VizieR-3?-source=VII/275/glade1) that are consistent with the position and distance at 3-sigma: ra dec sep dist sigma 323.124298 5.346313 0.42 85.3405 1.43 323.741486 5.792747 0.601 150.166 2.48 323.621368 6.034144 0.809 85.5611 2.71 323.298126 4.682521 0.594 173.891 2.88 (sep = separation in degrees). If we use the newer Glade 2.3 catalog (https://vizier.u-strasbg.fr/viz-bin/VizieR?-source=VII/281), we find only the first two objects as consistent within 3-sigma. Further observations of these galaxies are under way.