GCN Circular 26488
Subject
LIGO/Virgo S191213g: No counterpart candidate in the NOWT observations
Date
2019-12-18T18:31:43Z (4 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
Z.P. Zhu, B.Y. Yu, D. Xu (NAOC), X. Zhang, S.G. Ma, J.Z. Liu, H.B. Niu
(XAO), H.J. Wang, L. Ge, T.M. Zhang, X. Zhou, C.Z. Cui, Y.F. Xu (NAOC),
H.B. Zhao, B. Li (PMO), J.R. Mao
(YNAO), X. Gao (Urumqi No.1 Senior High School) report on behalf of the
GWFUNC collaboration:
We observed the high-probability localization region of the LIGO/Virgo
gravitational wave trigger S191216ap (GCN #26454) that can be reached by
the Nanshan One-meter Wide field Telescope (NOWT) with the FOV of
1.3x1.3 deg^2. Observations started at 11:57:05 UT and ended at 15:19:31
UT on 2019-12-17 in R-band. Typical limiting depth is of ~19.0 mag, and
60 sec for each exposure.
Listed below are the center coordinates of each exposure:
21:12:36.864000 +29:36:00.000000
21:18:35.424000 +29:36:00.000000
21:06:33.984000 +30:54:00.000000
21:18:40.608000 +30:54:00.000000
21:06:28.800000 +32:12:00.000000
21:12:36.864000 +32:12:00.000000
21:18:45.792000 +32:12:00.000000
21:12:19.584000 +25:42:00.000000
21:18:05.184000 +25:42:00.000000
21:23:51.648000 +25:42:00.000000
21:12:15.264000 +27:00:00.000000
21:18:05.184000 +27:00:00.000000
21:18:05.184000 +28:18:00.000000
21:23:59.424000 +28:18:00.000000
20:52:44.544000 +37:24:00.000000
21:05:50.784000 +37:24:00.000000
20:52:37.632000 +38:42:00.000000
21:05:57.696000 +38:42:00.000000
20:52:30.720000 +40:00:00.000000
20:59:17.664000 +40:00:00.000000
21:06:04.608000 +40:00:00.000000
21:06:22.752000 +21:48:00.000000
21:17:34.944000 +21:48:00.000000
21:06:18.432000 +23:06:00.000000
21:11:58.848000 +23:06:00.000000
21:06:15.840000 +24:24:00.000000
21:11:58.848000 +24:24:00.000000
21:17:40.992000 +24:24:00.000000
20:43:26.400000 +41:18:00.000000
20:50:21.984000 +41:18:00.000000
20:57:17.568000 +41:18:00.000000
20:43:17.760000 +42:36:00.000000
20:50:21.984000 +42:36:00.000000
20:57:25.344000 +42:36:00.000000
20:43:08.256000 +43:54:00.000000
20:50:21.984000 +43:54:00.000000
20:57:34.848000 +43:54:00.000000
20:47:35.232000 +33:30:00.000000
20:53:50.208000 +33:30:00.000000
21:00:04.320000 +33:30:00.000000
21:00:10.368000 +34:48:00.000000
20:47:24.864000 +36:06:00.000000
20:53:50.208000 +36:06:00.000000
21:00:16.416000 +36:06:00.000000
21:12:18.720000 +14:00:00.000000
21:17:40.992000 +14:00:00.000000
21:23:01.536000 +14:00:00.000000
21:12:16.992000 +15:18:00.000000
21:17:40.992000 +15:18:00.000000
21:23:03.264000 +15:18:00.000000
21:12:14.400000 +16:36:00.000000
21:23:05.856000 +16:36:00.000000
21:12:50.688000 +33:30:00.000000
21:19:04.800000 +33:30:00.000000
21:06:30.528000 +34:48:00.000000
21:12:50.688000 +34:48:00.000000
21:19:09.984000 +34:48:00.000000
21:06:23.616000 +36:06:00.000000
21:12:50.688000 +36:06:00.000000
21:06:28.800000 +17:54:00.000000
21:11:56.256000 +17:54:00.000000
21:17:23.712000 +17:54:00.000000
21:06:25.344000 +19:12:00.000000
21:11:56.256000 +19:12:00.000000
21:06:22.752000 +20:30:00.000000
21:22:59.808000 +17:54:00.000000
21:11:56.256000 +20:30:00.000000
21:28:27.264000 +17:54:00.000000
No credible counterpart candidate was identified in the above fields.
In addition, we also imaged the localization region of the HAWC
gamma-ray counterpart candidate (GCN #26472) during the searching, which
is inside the localization region of the IceCube neutrino counterpart
candidate (GCN #26460). Four out of nine GLADE galaxies were covered, as
follows:
| RAJ2000 | DEJ2000 | Dist | r_SDSS | r_NOWT |
| ---------- | --------- | ----- |-------- | ---------- |
| 323.482422 | +5.279632 | 274.4 | 16.50 | 16.52 |
| 323.056030 | +4.832057 | 219.1 | 15.83 | 15.84 |
| 323.173767 | +4.467985 | 292.5 | 16.10 | 16.20 |
| 323.034882 | +4.482058 | 340.7 | 16.24 | 16.13 |
All NOWT measurements are consistent with the SDSS values. Any
significant optical transient within these galaxies can be ruled out.
Furthermore, we imaged the HAWC region again, started at 13:09:43.0 UT
on 2019-12-18, with 200 s for each exposure in R-band. Our results are
as follows:
| RAJ2000 | DEJ2000 | Dist | r_SDSS | r_NOWT |
| ---------- | --------- | ----- |-------- | ---------- |
| 323.482422 | +5.279632 | 274.4 | 16.50 | 16.51 |
| 323.056030 | +4.832057 | 219.1 | 15.83 | 15.85 |
| 322.921936 | +5.503483 | 232.2 | 15.57 | 15.60 |
| 322.838806 | +5.255421 | 179.3 | 15.41 | 15.65 |
| 322.821228 | +5.553754 | 338.7 | 15.83 | 15.70 |
| 322.749084 | +5.108610 | 330.8 | 15.94 | 15.90 |
| 323.173767 | +4.467985 | 292.5 | 16.10 | 16.20 |
| 322.906006 | +5.850705 | 323.1 | 16.84 | 16.87 |
| 323.034882 | +4.482058 | 340.7 | 16.24 | 16.12 |
Again the NOWT measurements are consistent with the SDSS values. Any
significant optical transient within these galaxies can be ruled out.