[vsnet-grb-info 23566] LIGO/Virgo S190901ap: NOT spectroscopy of AT2019pjv

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25665
SUBJECT: LIGO/Virgo S190901ap: NOT spectroscopy of AT2019pjv
DATE:    19/09/05 10:25:51 GMT
FROM:    Erkki Kankare at University of Turku  <erkki.kankare at utu.fi>

E. Kankare (U. Turku), P. Lundqvist (Stockholm U.), R. Kotak, S. Mattila (U. Turku), M. A. P. Torres (IAC/ULL/SRON), T. Heikkilä, H. Kuncarayakti, T. Reynolds (U. Turku), S. Moran (NOT), D. Steeghs, J. Lyman (U. Warwick), T. Pursimo, J. Martikainen (NOT), report on behalf of a larger GOTO and NOT collaboration:

We obtained a spectrum of AT2019pjv discovered by MASTER (Lipunov et al., GCN #25649) that was also observed by GOTO (Ackley et al., GCN #25654) and HMT (Yu et al., GCN #25659) within the sky localization region of the LIGO/Virgo event S190901ap (LVC et al., GCN #25606, GCN #25614). 

The 1200 sec observation was obtained at the 2.56 m Nordic Optical Telescope equipped with ALFOSC, and started at 2019-09-04T20:42:48 (range 350-960 nm; resolution 1.6 nm). Reasonable matches are obtained using SNID (Blondin & Tonry, 2007, ApJ, 666, 1024) and template set 2.0 with SN 1991T-like type Ia SNe 2005eq, 1998es, 1999aa roughly 8 days before maximum at z = 0.013 +/- 0.007. Our classification confirms that previously reported by Nascimbeni et al. (GCN #25661). However, our redshift estimate is somewhat lower than that reported by Nascimbeni et al., but as we do not detect any narrow lines that could be from a putative host galaxy, we cannot fully exclude the possibility that AT2019pjv is not directly associated with MCG +05-41-001 at z = 0.023 (SDSS, DR12). This obviously has no effect on the main conclusion of Nascimbeni et al. that AT2019pjv is unrelated to S190901ap.

Based on observations taken with the Nordic Optical Telescope, operated by the Nordic Optical Telescope Scientific Association at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. The data presented here were obtained with ALFOSC, which is provided by the Instituto de Astrofisica de Andalucia (IAA) under a joint agreement with the University of Copenhagen and NOTSA.