ASAS-SN Discovery of a Likely R CrB Variable ASASSN-V J161156.22-575527.2
ATel #11017; T. Jayasinghe, K. Z. Stanek, C. S. Kochanek, J. V. Shields, T. A. Thompson (OSU), B. J. Shappee (Univ. of Hawaii), T. W.-S. Holoien (Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), Subo Dong (KIAA-PKU)
on 27 Nov 2017; 19:59 UT
Credential Certification: Krzysztof Stanek (firstname.lastname@example.org)
Subjects: Optical, Variables
As part of an ongoing effort by the ASAS-SN project (Shappee et
al. 2014; Kochanek et al. 2017) to characterize and catalog all bright
variable stars, we report the discovery of a likely Galactic R Coronae
Borealis (R CrB) variable.
The source ASASSN-V J161156.22-575527.2 (position from Gaia, g~13.3,
l=327.0719, b=-4.7824) was first observed by ASAS-SN on UT
2016-03-09. Presently, ASASSN-V J161156.22-575527.2 has more than
~390 V-band data points.
We noted the unusual variability of this object through the ASAS-SN
variability analysis pipeline (Jayasinghe et al. 2018, in prep).
The ASAS-SN Sky Patrol light curve shows that ASASSN-V
J161156.22-575527.2 displayed irregular variability with fluctuations
< ~0.5 mag up until a rapid, >2.5 mag photometric decline around MJD
2457772 (UT 2017-01-19). Such a large and rapid decline is typical of
dust production episodes in R CrB stars.
This source was previously flagged as a potential R CrB star based on
its WISE and 2MASS colors (Tisserand et al. 2012). Further
photometric and spectroscopic observations are encouraged.
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).