[vsnet-grb-info 22110] LIGO/Virgo S190425z: ZTF19aarzaod WHT spectroscopy

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24209
SUBJECT: LIGO/Virgo S190425z: ZTF19aarzaod WHT spectroscopy
DATE:    19/04/26 04:08:42 GMT
FROM:    Andrew Levan at U.of Leicester  <a.levan at astro.ru.nl>

K. Wiersema (Warwick), A.J. Levan (Radboud), M. Fraser (UCD), D.T.H. Steeghs (Warwick), P. Jonker (Radboud/SRON), D.B. Malesani (DAWN/NBI and DARK/NBI) and N.R. Tanvir (Leicester) report for a larger collaboration: 

"We obtained optical spectroscopy of ZTF19aarzaod (Kasliwal et al. GCN 24191) with the William Herschel Telescope (WHT) + ACAM spectrograph. Observations began at 01:34 UT for a total of 1200s and cover the wavelength range 4000-9000A. 

The spectrum shows a broad H-alpha feature at z=0.028 as noted by Buckley et al. (GCN 24205) and Izzo et al. (GCN 24208) which classifies it as an SN II, and indicates it is unlikely to be associated with LIGO/VIRGO S190425z. We note that despite its apparent origin as a core collapse supernova our spectra do not reveal any nebular emission lines close to the transient position that may be expected from the star formation that created the SN progenitor. 

We thank the WHT staff, in particular Lillian Dominguez for assistance with these observations ."