GCN Circular 21556
Subject
LIGO/Virgo G298048: REM optical/NIR observations
Date
2017-08-18T10:54:42Z (7 years ago)
From
Andrea Melandri at INAF-OAB <andy.melandri@gmail.com>
A. Melandri, P. D'Avanzo, S. Campana, S. Covino (INAF-OAB), G. Greco (Urbino University/INFN Firenze), M. Branchesi (GSSI), D. Fugazza (INAF-OAB), L. Amati (INAF-IASF Bo), L. A. Antonelli, (INAF-OAR), S. Ascenzi (INAF-OAR), M.T. Botticella (INAF-OAC), E. Cappellaro (INAF-OAPD), V. D'Elia (INAF-ASDC), F. Getman (INAF-OAC), A. Grado (INAF-OAC), L. Limatola (INAF-OAC), M. Lisi (INAF-OAR), L. Nicastro (INAF-IASF Bo), E. Palazzi (INAF-IAFS Bo), E. Pian (SNS-Pisa), S. Piranomonte (INAF-OAR), L. Pulone (INAF-OAR), A. Rossi (INAF-IASF Bo), G. Stratta (Urbino University/INFN Firenze), G. Tagliaferri (INAF-OAB), V. Testa (INAF-OAR), L . Tomasella (INAF-OAPD), S. Yang (INAF-OAPD), E. Brocato (INAF-OAR) on behalf of GRavitational Wave Inaf TeAm report:
We carried out optical/NIR follow-up observations of the LIGO/Virgo GW trigger G298048 (LVC GCN Circ. 21509, 21513) with the 60-cm robotic telescope REM located at the La Silla Observatory (Chile) by performing targeted observations of catalogued galaxies in the LVC skymap. The observations were carried out from 23:11:29 UT on 2017 Aug 17 (i.e. 10.5 hours after the event detection) to 02:08:24 UT on on 2017 Aug 18, simultaneously in the g, r, i, z and H bands.
We observed 18 galaxies (see table below). Group1 targets were selected within 3sigma from the position of the neutrino candidate reported in LVC GCN Circ. 21511, with a distance consistent with the GW trigger; Group2 targets are a sub-sample of the galaxies within the 50% probability region reported in the LVC GCN Circ. 21516; Group3 targets are galaxies reported in LVC GCN Circ. 21519, 21521.
RA(J2000) Dec(J2000) Distance (Mpc)
---Group1
12:04:20.16 -01:31:49.58 27.41
12:01:11.04 -01:17:43.30 28.19
12:13:38.88 -01:17:36.56 34.27
12:02:31.68 -02:18:11.52 40.08
12:16:44.16 -02:48:37.08 45.95
12:06:52.80 -04:02:36.96 26.25
12:00:24.96 -04:54:49.32 35.73 *
---------------------------------------
---Group2
12:57:27.90 -19:41:28.67 44.75
13:07:33.75 -24:00:30.98 43.94
13:08:04.32 -23:47:48.64 34.09
13:06:56.51 -23:55:01.45 33.65
13:07:05.97 -23:40:37.34 33.42
13:07:37.73 -23:34:44.11 41.75
13:06:24.01 -24:09:50.42 33.43
13:07:37.68 -23:56:18.11 45.98
13:06:19.39 -22:58:49.18 39.36
---------------------------------------
---Group3
13:09:47.68 -23:23:02.03 41.66
13:16:23.25 -26:33:41.03 45.59
*: we detected a possible optical source in this field at the following coordinates: RA(J2000),Dec(J2000) = 12:00:26.76,-04:55:04.2 (+/- 0.5"). This source is faint, having a magnitude of r~19.3 (i.e. close to the limiting magnitude of our observations) and we cannot establish the nature of this objects. However, its position seems to be consistent (within 3 arcmin) with a minor planet (23444-Kukucin).
A preliminary analysis (also based on visual comparison with the DSS) reveals no obvious optical/NIR candidate counterpart in the above galaxies down to the following magnitudes: r > 19.5, H > 17.0 (AB, 3sigma UL).