Spectroscopic confirmation of nova 2008-07a in M31
ATel #1773; E. Barsukova, O. Sholukhova, A. Valeev, S. Fabrika (Special Astrophysical Observatory, Russia), V. Goranskij (SAI, Moscow Univ.), W. Pietsch (MPE, Germany), K. Hornoch (Ondrejov Observatory, Czech Republic)
on 9 Oct 2008; 15:04 UT
Credential Certification: Barsukova E.A. (bars@sao.ru)
Subjects: Optical, Nova, Star, Variables
We obtained low resolution spectra of the optical nova candidate M31N 2008-07a (RA 00 42 34.42, Dec +41 18 15.7, J2000) discovered by M. Henze et al. (ATel #1609) on 2008 July 6.04 UT with an R magnitude of 18.7. Later the nova was discovered independently by K. Hornoch and P. Kusnirak (see CBAT_M31) on July 8. They found the nova on earlier frames dated on June 2.029 UT with an R magnitude of 19.0.
Three spectra were taken on 2008 Oct. 3.00 UT with the Russian 6-m telescope BTA equipped with the SCORPIO spectral camera. The spectral range was 390-755 nm, resolution 1.27 nm. On the time of
observations, we measured the star brightness using CCD frames of BTA as follows: R = 18.8, V = 19.1.
M31N 2008-07a shows the typical spectral and photometric behaviour of a slow FeII type nova. The emission lines of the Balmer series are strongest features in the spectrum. The equivalent width of H_alfa is equal to 11 nm. The H_alpha line profile has a FWHM of 450 km/s after correction for spectral resolution. The profile of H_beta is slightly broader (530 km/s). The heliocentric radial velocity of both of these lines is -120 km/s. With an S/N ratio of about 10 in the continuum of the total spectrum, numerous emission Fe II lines are visible as predominant non-Balmer lines.
Spectrum of M31N 2008-07a:
