[vsnet-grb-info 24392] LIGO/Virgo S191213g: NOT optical spectroscopy of AT2019wxt (PS19hgw)

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26491
SUBJECT: LIGO/Virgo S191213g: NOT optical spectroscopy of AT2019wxt (PS19hgw)
DATE:    19/12/18 22:17:55 GMT
FROM:    Daniele B Malesani at DTU Space  <malesani at space.dtu.dk>

L. Izzo (DARK/NBI), D. B. Malesani (DTU Space), K. E. Heintz (Univ. 
Iceland), J. Hjorth (DARK/NBI), B. Milvang-Jensen (DAWN/NBI), S. H. 
Bruun (DARK/NBI), G. Leloudas (DTU Space), S. Simon-Diaz (IAC; La 
Laguna), A. de Burgos (NOT; La Laguna), report on behalf of a larger 
collaboration:

We observed the faint transient AT 2019wxt (PS19hgw), spatially and 
temporally consistent with the gravitational wave event S191213g (LIGO 
and Virgo collaboration, GCN 26402), with the Nordic Optical Telescope 
(NOT) equipped with the ALFOSC instrument. A spectrum with 2400 s 
exposure was secured starting on 2019 Dec 18 at 19:52 UT (MJD 58835.83), 
covering the wavelength range 3200-9600 AA. Photometry yields i = 18.99 
+/- 0.02 mag (AB) calibrated against the Pan-STARRS catalog.

Our spectrum reveals a blue, mostly featureless continuum, which can be 
fit with a flat spectrum (F_nu propto nu^0). A narrow Halpha emission 
line is detected at z = 0.037, consistent with the catalogued value from 
NED, which we impute to emission from the underlying host galaxy. Our 
results are consistent with the findings of Dutta et al. (GCN 26490).

At the present stage, the classification of this transient is unclear 
and we encourage further spectroscopic and photometric follow-up.