FBS 0117+396 pulsating sdB star photometry

DOI

The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (MUCHFUSS) aims to discover subdwarf-B stars with massive compact companions such as overmassive white dwarfs (M>1.0M_{sun}_), neutron stars or black holes. From the 127 subdwarfs with substantial radial-velocity variations discovered in the initial survey, a number of interesting objects have been selected for extensive follow-up. After an initial photometry run with BUSCA revealed that FBS0117+396 is photometrically variable both on long and short timescales, we chose it as an auxiliary target during a 6-night multi-color photometry run with Ultracam. Spectroscopy was obtained at a number of observatories in order to determine the binary period and obtain a radial-velocity amplitude. After establishing an orbital period of P=0.252d, and removing the signal associated with the irradiated hemisphere of the M-dwarf companion, we were able to detect ten pulsation periods in the Fourier spectrum of the light curve. Two pulsation modes are found to have short periods of 337 and 379s, and at least eight modes are found with periods between 45-min and 2.5h. This establishes that FBS0117+396 is an sdB+dM reflection binary, in which the primary is a hybrid pulsator, and the first one found with this particular melange of flavours.

Identifier
DOI http://doi.org/10.26093/cds/vizier.35590035
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/A+A/559/A35
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/559/A35
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/559/A35
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/A+A/559/A35
Provenance
Creator Ostensen R.H.; Geier S.; Schaffenroth V.; Telting J.H.; Bloemen S.,Nemeth P.; Beck P.G.; Lombaert R.; Papics P.I.; Tillich A.; Ziegerer E.,Fox Machado L.; Littlefair S.; Dhillon V.; Aerts C.; Heber U.,Maxted P.F.L.; Gansicke B.T.; Marsh T.R.
Publisher CDS
Publication Year 2013
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy