GCN Circular 24479
Subject
LIGO/Virgo S190510g : Xinglong-60cm upper limit of the GRAWITA REM's OT
Date
2019-05-11T10:40:06Z (6 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
Z.P. Zhu, D. Xu, B.Y. Yu, J.J. Ren, T.M. Zhang, X. Zhou, H.J. Wang, C.Z.
Cui, D.W. Fan, Y.F. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School),
S. Yang (INAF-OAPd), H.B. Zhao, B. Li (PMO), J.Z. Liu, H.B. Niu (XAO),
J.R. Mao, J.M. Bai (YNAO), report on behalf of the GWFUNC collaboration:
We observed the optical transient (OT), r = 17.3 +/- 0.1 (AB, calibrated
against
the SDSS), in P. D'Avanzo et al. (GCN 24455) of the gravitational-wave
event S190510g (GCN 24442) using the Xinglong-60cm telescope located at
Xinglong, Hebei, China.
The OT is ~20" away from the SDSS galaxy, SDSS J142914.95+094059.4,
which has a photoZ=0.041 +/- 0.0149, corresponding to a luminosity
distance of 182.2 Mpc, thus being consistent with the LIGO's luminosity
distance estimate of 227 +/- 92 Mpc (GCN 24448). At the above redshift,
SDSS J142914.95+094059.4 has an absolute magnitude of M(r) = 17.92-36.30
= -18.38, at the border of dwarf/normal galaxies. The OT is ~16.3 kpc
away from the nucleus of the SDSS galaxy, much larger than usual radii
of such galaxies. If double neutron stars are considered having been
kicked out of their host galaxy earlier before, such a scenario might be
possible.
Under the above assumption, we obtained 15x360 s frames in R band,
started at 16:12:27 on 2019-05-10, i.e., about 10 hr after the OT
detected. The OT has decayed and is not detected in our stacked image of
5400 s, down to a limiting magnitude of r ~ 20.6, calibrated with the
SDSS field.