[vsnet-grb-info 23444] LIGO/Virgo S190814bv: AT2019nxe and AT2019obc 10.4m GTC spectroscopy

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25543
SUBJECT: LIGO/Virgo S190814bv: AT2019nxe and AT2019obc 10.4m GTC spectroscopy
DATE:    19/08/29 12:19:30 GMT
FROM:    Alberto J. Castro-Tirado at IAA-CSIC  <ajct at iaa.es>

A. J. Castro-Tirado (IAA-CSIC), A. F. Valeev (SAO-RAS), Y.-D. Hu 
(IAA-CSIC),
E. Fernandez-Garcia (IAA-CSIC), V. V. Sokolov (SAO-RAS), I. Carrasco and
A. Castellon (UMA), D. L. Tucker (Fermilab), M. Soares-Santos (Brandeis 
U)
and S. Geier (GRANTECAN, IAC, ULL), on behalf of a larger collaboration, 
report:

Following the detection of desgw-190814j (AT2019nxe) (Soares-Santos et 
al.,
GCNC 25425) and desgw-190814q (AT2019obc) (Soares-Santos et al., GCNC 
25438 )
within the error area of the GW event S190814bv (LVC, GCNC 25324), we 
obtained
imaging and optical spectra covering the range 5100-10000 A with the 
10.4m GTC
telescope equipped with OSIRIS in La Palma (Spain) starting on Aug 23, 
02:10 UT.

AT2019nxe is located 1.8 arcsec away from the center of the host galaxy 
and on
Aug 23, 02:15 UT the magnitude was measured to be r = 20.39 +/- 0.07. 
The spectrum
(broad lines) is consistent with a SNIa near the maximum at the nearby 
host galaxy
redshift (z = 0.0777 +/- 0.0005, based on the narrow emission lines from 
the galaxy).

AT2019obc is located 1.8 arcsec away from the center of the host galaxy. 
Cross-
correlating the spectrum (broad lines) with supernova template spectra 
in SNID
(Blondin & Tonry, 2007), we find a good match to the spectra of SNIa at 
few days
post maximum at a redshift of 0.216 +/- 0.005.

Therefore we consider that both AT2019nxe and AT2019obc are unrelated to 
the GW
event S190814bv.