GCN Circular 27075
Subject
LIGO/Virgo S200213t: P200 Spectroscopy of ZTF20aanakcd/AT2020cmr
Date
2020-02-15T06:23:56Z (5 years ago)
From
Igor Andreoni at Caltech <igor.andreoni@gmail.com>
Igor Andreoni (Caltech), Kishalay De (Caltech), Mansi Kasliwal (Caltech), Yang Huang (Yunnan Univ.), Xiaowei Liu (Yunnan Univ.)
On behalf of the GROWTH collaboration
On 2020-02-15 03:30 UT, we used the Double Beam Spectrograph (Oke & Gunn 1982) on the Palomar 200-inch telescope to observe ZTF20aanakcd/AT2020cmr (Reusch et al., GCN #27068), a transient discovered with the Zwicky Transient Facility (Graham et al., 2019; Bellm et al., 2019) during the follow-up of the binary neutron star merger candidate S200213t (LVC, GCN #2704).
The optical spectrum shows intermediate width Balmer emission features consistent with a Type IIn supernova at z=0.077. We also confirmed that the redshift of the transient is consistent with the host galaxy redshift, extracted from the same observations, based on the analysis of Balmer and [S II] lines. We conclude that ZTF20aanakcd/AT2020cmr is unrelated to S200213t.