Artykuł w czasopiśmie
Brak miniatury
Licencja

 

Mass and p-factor of the Type II Cepheid OGLE-LMC-T2CEP-098 in a Binary System

dc.abstract.enWe present the results of a study of the type II Cepheid (P <SUB>puls</SUB> = 4.974 days) in the eclipsing binary system OGLE-LMC-T2CEP-098 (P <SUB>orb</SUB> = 397.2 days). The Cepheid belongs to the peculiar W Vir group, for which the evolutionary status is virtually unknown. It is the first single-lined system with a pulsating component analyzed using the method developed by Pilecki et al. We show that the presence of a pulsator makes it possible to derive accurate physical parameters of the stars even if radial velocities can be measured for only one of the components. We have used four different methods to limit and estimate the physical parameters, eventually obtaining precise results by combining pulsation theory with the spectroscopic and photometric solutions. The Cepheid radius, mass, and temperature are 25.3+/- 0.2 {R}<SUB>⊙ </SUB>, 1.51+/- 0.09 {M}<SUB>⊙ </SUB>, and 5300+/- 100 {{K}}, respectively, while its companion has a similar size (26.3 {R}<SUB>⊙ </SUB>), but is more massive (6.8 {M}<SUB>⊙ </SUB>) and hotter (9500 K). Our best estimate for the p-factor of the Cepheid is 1.30+/- 0.03. The mass, position on the period-luminosity diagram, and pulsation amplitude indicate that the pulsating component is very similar to the Anomalous Cepheids, although it has a much longer period and is redder in color. The very unusual combination of the components suggest that the system has passed through a mass-transfer phase in its evolution. More complicated internal structure would then explain its peculiarity. This paper includes data gathered with the 6.5 m Magellan Clay Telescope at Las Campanas Observatory, Chile.
dc.affiliationUniwersytet Warszawski
dc.contributor.authorPilecki, Bogumił
dc.contributor.authorGieren, Wolfgang
dc.contributor.authorSmolec, Radosław
dc.contributor.authorPietrzyński, Grzegorz
dc.contributor.authorThompson, Ian B.
dc.contributor.authorAnderson, Richard I.
dc.contributor.authorBono, Giuseppe
dc.contributor.authorSoszyński, Igor
dc.contributor.authorKervella, Pierre
dc.contributor.authorNardetto, Nicolas
dc.contributor.authorTaormina, Mónica
dc.contributor.authorStępień, Kazimierz
dc.contributor.authorWielgórski, Piotr
dc.date.accessioned2024-01-25T05:33:48Z
dc.date.available2024-01-25T05:33:48Z
dc.date.copyright2017-04-25
dc.date.issued2017
dc.description.accesstimeBEFORE_PUBLICATION
dc.description.financeNie dotyczy
dc.description.number2
dc.description.versionORIGINAL_AUTHOR
dc.description.volume842
dc.identifier.doi10.3847/1538-4357/AA6FF7
dc.identifier.issn0004-637X
dc.identifier.urihttps://repozytorium.uw.edu.pl//handle/item/111892
dc.identifier.weblinkhttp://adsabs.harvard.edu/abs/2017ApJ...842..110P
dc.languageeng
dc.pbn.affiliationastronomy
dc.relation.ispartofAstrophysical Journal
dc.relation.pages110
dc.rightsOther
dc.sciencecloudnosend
dc.titleMass and p-factor of the Type II Cepheid OGLE-LMC-T2CEP-098 in a Binary System
dc.typeJournalArticle
dspace.entity.typePublication