ASASSN-18abj is a Dwarf Nova
ATel #12295; Frederick M Walter (Stony Brook University)
on 14 Dec 2018; 14:49 UT
Credential Certification: Fred Walter (frederick.walter@stonybrook.edu)
Subjects: Optical, Cataclysmic Variable, Nova, Transient, Variables
The optical transient ASASSN-18abj was reported by R. Fidrich in vsnet-alert 22827.
On the basis of the large amplitude outburst,
Fidrich suggested it could be a galactic nova or a nearby CV.
R. Hinojosa and L. Paredes obtained a spectrum with the SMARTS Chiron
fiber-fed high resolution spectrograph at 0527UT on 2018 Dec 14.
The integration time was 10 minutes; the resolution is 27,800.
The spectrum shown a blue continuum. Hα is in emission
above the continuum
with an equivalent width of -3.6Å and a full width at zero intensity of
9.7Å. The central velocity of the line is -12 km/s. The line has a narrow central reversal with a
depth of 20% of the emission line intensity.
The Hβ line has a centrally-reversed emission reversal (equivalent
width -0.5Å); the absorption line FWZI is about 27Å.
Hγ and Hδ are in absorption. There is possible broad He II
λ 4686 emission above the continuum (equivalent
width -1.5Å; the FWHM is about 10Å).
The spectrum is available at the link below.
ASASSN-18abj is not a galactic nova; the spectrum is that of a dwarf nova in outburst.
This is consistent with the conclusion of Sokolosky et al. (ATel #12294) that the
transient is nearby.
link to spectrum
