[vsnet-grb-info 24603] LIGO/Virgo S200105ae: AT2020pp and AT2020py 10.4m GTC spectroscopy

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26702
SUBJECT: LIGO/Virgo S200105ae: AT2020pp and AT2020py 10.4m GTC spectroscopy
DATE:    20/01/11 11:34:38 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 and E. 
Fernandez-Garcia (IAA-CSIC), V. Sokolov (SAO-RAS), I. Carrasco and A. 
Castellon (UMA), S. Anand (Caltech) and J. Font (GRANTECAN, IAC, ULL), 
on behalf of a larger collaboration, report:

Following the detection of AT2020pp/ZTF20aaervoa, and 
AT2020py/ZTF20aaerxsd (Stein et al. GCNC 26673) within the error area of 
the GW event S200105ae (LVC, GCNC 26640), 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 Jan 10, 04:17 UT, under poor 
seeing conditions.

For AT2020pp/ZTF20aaervoa, the GTC spectrum is consistent with a SN IIP 
at about 3 days after maximum at redshift z = 0.046 +/- 0.003, 
consistent with the redshift of the host galaxy derived from the 
emission lines (z = 0.0448 +/- 0.0005).

For AT2020py/ZTF20aaerxsd, the GTC spectrum is consistent with a SN Ia  
at about 3 days after maximum at redshift z = 0.055 +- 0.005, consistent 
with the redshift of the host galaxy derived from the emission lines (z 
=  0.0533 +/- 0.0005).

Therefore we consider that neither AT2020pp/ZTF20aaervoa nor 
AT2020py/ZTF20aaerxsd are related to the S200105ae GW alert.

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