Variability of Galactic Be stars using ASAS-3

We present an investigation of a large sample of confirmed (N=233) and candidate (N=54) Galactic classical Be stars (mean V magnitude range of 6.4-12.6mag), with the main aim of characterizing their photometric variability. Our sample stars were preselected among early-type variables using light-curve morphology criteria. Spectroscopic information was gleaned from the literature, and archival and newly acquired spectra. Photometric variability was analysed using archival ASAS-3 time-series data. To enable a comparison of results, we have largely adopted the methodology of Labadie-Bartz et al. (2017AJ....153..252L, Cat. J/AJ/153/252), who carried out a similar investigation based on KELT data. Complex photometric variations were established in most stars: outbursts on different time-scales (in 73+/-5 per cent of stars), long-term variations (36+/-6 per cent), periodic variations on intermediate time-scales (1+/-1 per cent), and short-term periodic variations (6+/-3 per cent). 24+/-6 per cent of the outbursting stars exhibit (semi)periodic outbursts. We close the apparent void of rare outbursters reported by Labadie-Bartz et al. (2017AJ....153..252L, Cat. J/AJ/153/252) and show that Be stars with infrequent outbursts are not rare. While we do not find a significant difference in the percentage of stars showing outbursts among early-type, mid-type, and late-type Be stars, we show that early-type Be stars exhibit much more frequent outbursts. We have measured rising and falling times for well-covered and well-defined outbursts. Nearly all outburst events are characterized by falling times that exceed the rising times. No differences were found between early-, mid-, and late-type stars; a single non-linear function adequately describes the ratio of falling time to rising time across all spectral subtypes, with the ratio being larger for short events.

Cone search capability for table J/MNRAS/479/2909/tablea1 (Essential data for our stars, sorted by increasing right ascension)

Identifier
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/MNRAS/479/2909
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/479/2909
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/479/2909
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/MNRAS/479/2909
Provenance
Creator Bernhard K.; Otero S.; Hummerich S.; Kaltcheva N.; Paunzen E.; Bohlsen T.
Publisher CDS
Publication Year 2022
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