Liverpool Telescope Spectra of M31N 2015-05b (PNV J00431911+4116082)
ATel #7580; S. C. Williams (LJMU), M. J. Darnley (LJMU), M. F. Bode (LJMU), A. W. Shafter (SDSU)
on 30 May 2015; 18:35 UT
Credential Certification: Matt Darnley (M.J.Darnley@ljmu.ac.uk)
Referred to by ATel #: 7789
We report spectroscopic observations of the M31 nova candidate M31N 2015-05b (PNV J00431911+4116082; ATel #7554, #7564) taken with the SPRAT low-resolution spectrograph on the Liverpool Telescope (Steele et al. 2004).
We obtained the first spectrum on 2015 May 24.2 UT. The only features clearly distinguishable are the Balmer lines. Hα is seen in emission with a P-Cygni absorption profile and only absorption is detected for Hβ and Hγ.
In our second spectrum, taken 2015 May 30.2 UT, absorption profiles are no longer clearly detected, with Hα, Hβ and Hγ all seen in emission. We calculate the FWHM of Hα in this second spectrum to be 1700 ± 100 km/s. In addition to the Balmer series, we also detect numerous Fe II and O I (7773 Å) emission lines.
These spectra confirm that the transient is a nova in M31 and a member of the Fe II spectroscopic class (Williams 1992).
