Spectroscopic Confirmation of the Recent M31 Nova Candidate, M31N 2008-11a
ATel #1832; A. W. Shafter (SDSU), R. Ciardullo (PSU), M. F. Bode, M. J. Darnley (Liverpool JMU, UK), K. A. Misselt (U. Arizona)
on 7 Nov 2008; 02:30 UT
Credential Certification: Allen W. Shafter (aws@nova.sdsu.edu)
Subjects: Optical, Nova, Transient
The recent M31 nova candidate, M31N 2008-11a, was discovered
by K. Nishiyama and F. Kabashima on 2008 November 04.534 UT, and independently
by K. Hornoch on 2008 November 4.718 UT.
At our request, a spectrum (420-720 nm) of M31N 2008-11a
was obtained approximately two days later
on 2008 November 6.3 UT
by J. Caldwell and C. Terrazas
with the 9.2m Hobby-Eberly Telescope
(+ Marcario Low-Resolution Spectrograph).
The spectrum of M31N 2008-11a is dominated by broad Balmer and He I
emission features (FWHM H&alpha ~ 5000 km/s)
superimposed on a flat continuum. Other weaker emission features
are also present, including a blend of N III (4640Ã
) and He II (4686Ã
).
In addition, there are two broad emission features to the red of the H&beta line.
The first feature is likely a blend of N II (5001Ã
),
He I (5016Ã
), and possibly Fe II (5018Ã
), while a second feature
near 5170Ã
is likely due solely to Fe II. We are tempted to classify
M31N 2008-11a as a He/N nova, but given
the likely detection of Fe II emission, it would be more accurate
to classify it as a "hybrid" nova (see Williams, 1992, AJ, 104, 725). Hybrid novae often
evolve into He/N novae within a few weeks after eruption,
and further spectroscopic observations are encouraged to see if M31N 2008-11a
follows this path.
