Spectroscopic observation of the transient ZTF19acnfsij/AT2019uiz in M31

ATel #13317; Monika Soraisam (NCSA/UIUC), Chien-Hsiu Lee (NSF OIR Lab), Rafael Nunez, Kevin McKinnon, Puragra Guhathakurta (UCSC), Thomas Matheson, Abhijit Saha (NSF OIR Lab), WeiKang Zheng, Alexei V. Filippenko (UC Berkeley), Chien-Chu Wei (UCSC)
on 28 Nov 2019; 17:57 UT
Credential Certification: Monika Soraisam (soraisam@noao.edu)

Subjects: Optical, Cataclysmic Variable, Nova, Transient

We report the spectroscopic observation of the transient ZTF19acnfsij/AT2019uiz in M31. It was flagged by a filter on the ANTARES alert-broker (https://antares.noao.edu/) customized to find promising stellar explosive events from the ZTF public alert stream.

Name          | Alternative name |    RA (J2000)     |    Dec (J2000)    |    First detection: MJD, mag 
ZTF19acnfsij  | AT2019uiz        |    00:42:30.37    |    41:03:29.17    |    58793.124537,   R~18.4+/-0.07 

On 2019 Nov. 21 UT, we obtained the spectrum of this source with the Kast double spectrograph on the Shane 3 m telescope at Lick Observatory via a ToO program (2019B_S040; PI Guhathakurta). The spectrum shows prominent Balmer emission lines, with the full width at half-maximum intensity of the H-alpha line around 1700 km/s, along with emission lines of O I as well as from the Paschen series between 8590 and 8900 . The transient is, thus, likely a nova in M31. Its light curve can be accessed at https://antares.noao.edu/alerts/locus/6339399.

We thank the staff of Lick Observatory, in particular, Dan Espinosa and Dr. Elinor Gates, for their help in executing the ToO observation.