TITLE:   GCN CIRCULAR
NUMBER:  27060
SUBJECT: LIGO/Virgo S200213t: AT2020ciy/ZTF20aamvqxl, AT2020cjg/ZTF20aamvoxx and AT2020cje/ZTF20aamvtip 10.4m GTC spectroscopy
DATE:    20/02/13 23:06:46 GMT
FROM:    Alberto J. Castro-Tirado at IAA-CSIC  <ajct@iaa.es>

A. F. Valeev (SAO-RAS), Y.-D. Hu, A. J. Castro-Tirado and E. 
Fernandez-Garcia (IAA-CSIC), V. Sokolov (SAO-RAS), I. Carrasco and A. 
Castellon (UMA) and G. Lombardi (GRANTECAN, IAC, ULL), on behalf of a 
larger collaboration, report:

Following the detection of AT2020ciy/ZTF20aamvqxl, 
AT2020cjg/ZTF20aamvoxx and AT2020cje/ZTF20aamvtip (Kasliwal et al. GCNC 
27051) within the error area of the GW event S200213t (LVC, GCNC 27042), 
we obtained optical spectra covering the range 3700-7400 A with the 
10.4m GTC telescope equipped with OSIRIS in La Palma (Spain) starting on 
Feb 13, 20:08 UT. Details follow:

AT2020ciy/ZTF20aamvqxl, a magnitude r'=20.04 +/- 0.03 on 21:29UT is 
derived. The GTC spectrum is consistent with a SNIa at redshift z = 
0.1018 +/- 0.0005.

AT2020cjg/ZTF20aamvoxx, a magnitude r'=18.19 +/- 0.07 on 20:33UT is 
derived. The GTC spectrum is consistent with a SNIa at redshift z = 
0.097 +/- 0.005.

AT2020cje/ZTF20aamvtip, a magnitude r'=20.08 +/- 0.02 on 20:55UT is 
derived. The GTC spectrum is consistent with a SNIa at redshift z = 
0.1512 +/- 0.0005.

Therefore we consider that AT2020ciy/ZTF20aamvqxl, 
AT2020cjg/ZTF20aamvoxx and AT2020cje/ZTF20aamvtip are unrelated to the 
S200213t GW alert.