ASAS-SN Discovery of a Bright Be Star Undergoing a Possible Outburst
ATel #10710; T. Jayasinghe, K. Z. Stanek, C. S. Kochanek (OSU), J. Thorstensen (Dartmouth), J. Rupert (MDM Observatory), J. L. Prieto (Diego Portales; MAS), J. V. Shields, T. A. Thompson (OSU), T. W.-S. Holoien, B. J. Shappee (Carnegie Observatories), Subo Dong (KIAA-PKU)
on 5 Sep 2017; 17:31 UT
Credential Certification: Krzysztof Stanek (stanek.32@osu.edu)
Subjects: Optical, Variables
As part of an ongoing effort by ASAS-SN project (Shappee et al. 2014;
Kochanek et al. 2017) to characterize and catalog all bright variable
stars (e.g., Jayasinghe et al. 2017, ATel #10634, #10677), we report the
discovery of a bright Be star undergoing a possible outburst.
The source ASASSN-V J010932.93+614659.0 (position from Gaia, g~12.1,
parallax=0.60 +/- 0.33 mas) is a Tycho2 source that was previously
classified as a K02 subgiant using a best-fit synthetic spectrum
(Pickles & Depagne 2010). The ASAS-SN light curve shows a current brightening event (~0.3 mag) over a period of >320 days.
A low resolution spectrum of ASASSN-V
J010932.93+614659.0 was obtained with the MDM 2.4m telescope + OSMOS
spectrometer(range 3960-6850 Angstroms; FWHM res. 4 Angstroms) on the
30th of August 2017. The
spectrum shows Balmer and He I lines in absorption and strong
narrow H-alpha in emission, characteristic of a Be-type star.
We thank Las Cumbres Observatory and its staff for their continued
support of ASAS-SN. ASAS-SN is funded in part by the Gordon and Betty
Moore Foundation through grant GBMF5490 to the Ohio State University,
NSF grant AST-1515927, the Mt. Cuba Astronomical Foundation, the
Center for Cosmology and AstroParticle Physics (CCAPP) at OSU, and the
Chinese Academy of Sciences South America Center for Astronomy
(CASSACA).
