Spectroscopic classification of PNV J00420765+4119438 and PNV J00425261+4118409 as nova eruptions in M31
ATel #11866; M. Sitaram (University of Maryland), M. J. Darnley (LJMU)
on 18 Jul 2018; 14:33 UT
Credential Certification: Matt Darnley (M.J.Darnley@ljmu.ac.uk)
Subjects: Optical, Nova, Transient
We obtained a spectrum of classical nova candidate PNV J00420765+4119438 (see CBAT TOCP and ATel #11849) with the SPRAT spectrograph (resolution R~350; Piascik et al. 2014) on the 2-m Liverpool Telescope (Steele et al. 2004) on 2018 July 14.09 UT. A spectrum of PNV J00425261+4118409 (ATel #11856) was taken on 2018 July 16.17 UT.
Both spectra show strong Balmer emission lines (Hα to Hδ). The FWHM of the Hα emission line is ~2700 km/s for PNV J00420765+4119438 and ~850 km/s for PNV J00425261+4118409.
The spectrum of PNV J00420765+4119438 also shows Fe II emission lines (multiple 42), along with possibly O I (7773 Å). The continuum of PNV J00420765+4119438 is relatively flat.
Other than Balmer emission, PNV J00425261+4118409 exhibits a featureless but blue continuum.
We conclude that both PNV J00420765+4119438 and PNV J00425261+4118409 are classical nova eruptions in M31. PNV J00420765+4119438 likely belongs to the Fe II taxonomic class, whereas PNV J00425261+4118409 was probably caught during the final rise or around peak luminosity. Follow-up observations are, as always, encouraged.
This summer internship project is supported by the GROWTH project funded by the National Science Foundation under Grant No 1545949.
