Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 26405

LIGO/Virgo S191205ah: AT2019wfa 10.4m GTC spectroscopy
2019-12-13T07:19:30Z (4 years ago)
Alberto J. Castro-Tirado at IAA-CSIC <>
Y.-D. Hu (IAA-CSIC), A. F. Valeev (SAO-RAS), A. J. Castro-Tirado and E. 
Fernandez-Garcia (IAA-CSIC), V. Sokolov (SAO-RAS), I. Carrasco and A. 
Castellon (UMA) and R. Scarpa (GRANTECAN, IAC, ULL), on behalf of a 
larger collaboration, report:

Following the detection of Gaia19fmm (AT2019wfa, Kostrzewa-Rutkowska et 
al. GCNC 26397) within the error area of the GW event S191205ah (LVC, 
GCNC 26350), 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 Dec 12, 21:00 UT.

For Gaia19fmm/AT2019wfa a magnitude r' = 18.01 +/- 0.02 on MJD 
58829.8727669 is derived. The GTC spectrum is consistent with a SN Ia 
3-4 days before maximum at redshift z = 0.0599 +/- 0.0005 derived from 
the emission lines of the host galaxy.

Therefore we consider that Gaia19fmm/AT2019wfa is unrelated to the 
S191205ah GW alert.
Looking for U.S. government information and services? Visit