AX Per UBVRI photometry

DOI

AX Per is an eclipsing symbiotic binary. During active phases, deep narrow minima are observed in its light curve, and the ionization structure in the binary changes significantly. From ~2007.5, AX Per entered a new active phase. We aim to derive the ionization structure in the binary and its changes during the recent active phase. We used optical high- and low-resolution spectroscopy and UBVRcIc photometry. We modeled the SED in the optical and broad wings of the H alpha line profile during the 2007-10 higher level of the AX Per activity. After 10 orbital cycles (~18.6 years), we again measured the eclipse of the hot component by its giant companion in the light curve. We derived a radius of 27+/-2R_{sun} for the eclipsed object and 115+/-2R{sun} for the eclipsing cool giant. The new active phase was connected with a significant enhancement of the hot star wind. From quiescence to activity, the mass-loss rate increased from ~9E-8 to ~3E-6M{sun}/yr, respectively. The wind causes the emission of the He++ zone, located in the vicinity of the hot star, and also is the reason for the fraction of the [OIII] zone at farther distances. Simultaneously, we identified a variable optically thick warm (T_eff~6000K) source that contributes markedly to the composite spectrum. The source was located at the hot star's equator and has the form of a flared disk, whose outer rim simulates the warm photosphere. The formation of the neutral disk-like zone around the accretor during the active phase was connected with its enhanced wind. It is probable that this connection represents a common origin of the warm pseudophotospheres that are indicated during the active phases of symbiotic stars.

Identifier
DOI http://doi.org/10.26093/cds/vizier.35360027
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/A+A/536/A27
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/536/A27
Related Identifier https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/536/A27
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/A+A/536/A27
Provenance
Creator Skopal A.; Tarasova T.N.; Carikova Z.; Castellani F.; Cherini G.,Dallaporta S.; Frigo A.; Marangoni C.; Moretti S.; Munari U.; Righetti G.L.,Siviero A.; Tomaselli S.; Vagnozzi A.; Valisa P.
Publisher CDS
Publication Year 2011
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