[vsnet-grb-info 24283] LIGO/Virgo S191205ah: MASTER OT 1.5m OSN imaging and 10.4m GTC spectroscopy

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26382
SUBJECT: LIGO/Virgo S191205ah: MASTER OT 1.5m OSN imaging and 10.4m GTC spectroscopy
DATE:    19/12/08 07:13:28 GMT
FROM:    Alberto J. Castro-Tirado at IAA-CSIC  <ajct at iaa.es>

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

Following the detection of MASTER OT J123123.61-043847.2 (Lipunov al. 
GCNC 26379, Murata et al. GCN 26381) within the error area of the GW 
event S191205ah (LVC, GCNC 26350), we obtained imaging at the 1.5m OSN 
telescope in Granada (Spain) and optical spectra covering the range 
3700-10000 A with the 10.4m GTC telescope equipped with OSIRIS in La 
Palma (Spain)
starting on Dec 8, 05:20 UT.

For MASTER OT J123123.61-043847.2 a magnitude r' = 17.9 on Dec 8, 05:20 
UT is derived. The GTC spectrum is consistent with a type Ia SN at 
redshift z = 0.056 +/- 0.003, implying an absolute optical magnitude 
close to the expected absolute magnitude at peak of type Ia SNe (M_V = 
-19.3).

Therefore we consider that MASTER OT J123123.61-043847.2 is unrelated to 
the S191205ah GW alert.