TITLE:   GCN CIRCULAR
NUMBER:  25325
SUBJECT: LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
DATE:    19/08/15 03:52:38 GMT
FROM:    Daniele B Malesani at DTU Space  <malesani@space.dtu.dk>

Kasper E. Heintz (Univ. Iceland), Daniele B. Malesani (DTU Space), 
Jonatan Selsing (Novo Nordisk), Andrew J. Levan (Radboud Univ.), Paolo 
D'Avanzo (INAF/OABr), Daniel A. Perley (LJMU), Lana Salmon (UCD), Ana 
Sagues Carracedo (OKC Stockholm), Silvia Piranomonte (INAF/OAR),  A. 
Amanda Djupvik (NOT), Luca Malavolta (INAF/OACt), report on behalf of a 
larger collaboration:

We observed the position of the 20 galaxies listed below, using the 
Nordic Optical Telescope equipped with the ALFOSC instrument. These 
argets were selected from the list of probable host galaxies generated 
by the HOGWARTS code (https://gwtool.watchertelescope.ie/), consistent 
with the 90% probability region of S190814bv (LIGO Scientific 
Collaboration and Virgo Collaboration, GCN 25324). Similar lists were 
coordinated with collaborating telescopes in La Palma: the Telescopio 
Nazionale Galileo, the Liverpool Telescope, and the William Hershel 
Telescope.

Each galaxy was observed for 2 minutes exposure in the SDSS r filter. 
Observations started as soon as the targets were observable, around 2019 
August 15.06 UT (4.3 hr after the GW event). Conditions were affected by 
the nearby bright Moon and large airmass.

Visual inspection of the 20 fields does not reveal any new candidate 
compared with the deeper archival images from the Pan-STARRS survey. The 
typical limiting magnitude is r ~ 21 (3 sigma), though we caution that 
the actual limit is shallower at locations superimposed on the brightest 
parts of the targeted galaxies. This corresponds to an absolute 
magnitude M_r > -16.2 at a distance of 276 Mpc.

List of target fields (RA, Dec)
00:47:07.527 -24:22:14.33
00:55:13.534 -26:19:16.51
00:50:54.447 -23:37:54.79
00:47:05.254 -24:14:19.33
00:55:09.151 -25:27:20.53
00:50:57.715 -23:33:28.78
00:50:09.705 -23:16:48.17
00:55:13.061 -24:02:38.52
00:48:58.272 -25:41:36.42
00:49:41.726 -25:03:02.93
00:48:24.757 -25:35:44.55
00:54:15.943 -23:32:06.58
00:44:13.189 -24:19:39.27
00:51:21.179 -26:59:22.02
00:46:13.218 -25:57:00.68
00:49:23.120 -26:30:26.99
00:50:12.393 -25:58:30.57
00:45:34.992 -24:14:54.74
00:47:52.584 -25:50:29.04
01:29:10.270 -31:34:41.63

[GCN OPS NOTE(15aug19): Per author's request, in the author list "Sagues-Corracedo"
was changed to "Sagues Carracedo".]