Mass and p-factor of the type II cepheid OGLE-LMC-T2CEP-098 in a Binary System
Author
dc.contributor.author
Pilecki, Bogumil
Author
dc.contributor.author
Gieren, Wolfgang
Author
dc.contributor.author
Smolec, Radoslaw
Author
dc.contributor.author
Pietrzynski, Grzegorz
Author
dc.contributor.author
Thompson, Ian B.
Author
dc.contributor.author
Anderson, Richard I.
Author
dc.contributor.author
Bono, Giuseppe
Author
dc.contributor.author
Soszynski, Igor
Author
dc.contributor.author
Kervella, Pierre
Author
dc.contributor.author
Nardetto, Nicolás
Author
dc.contributor.author
Taormina, Mónica
Author
dc.contributor.author
Stepien, Kazimierz
Author
dc.contributor.author
Wielgorski, Piotr
Admission date
dc.date.accessioned
2018-05-16T21:32:37Z
Available date
dc.date.available
2018-05-16T21:32:37Z
Publication date
dc.date.issued
2017
Cita de ítem
dc.identifier.citation
The Astrophysical Journal, 842:110 (16pp), 2017 June 20
es_ES
Identifier
dc.identifier.other
10.3847/1538-4357/aa6ff7
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/147835
Abstract
dc.description.abstract
We present the results of a study of the type II Cepheid (P-puls = 4.974 days) in the eclipsing binary system OGLELMC- T2CEP-098 (P-orb = 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-circle dot, 1.51 +/- 0.09 M-circle dot, and 5300 +/- 100 K, respectively, while its companion has a similar size (26.3 R-circle dot), but is more massive (6.8 M-circle dot) 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.
es_ES
Patrocinador
dc.description.sponsorship
Polish National Science Center, SONATA 2014/15/D/ST9/02248 / BASAL Centro de Astrofisica y Tecnologias Afines,
CATA PFB-06/2007 /
Chilean Ministry of Economy, Development and Tourism's Millennium Science Initiative, IC120009 / French Agence Nationale de la Recherche (ANR), ANR-15-CE31-0012-01 /
European Research Council (ERC) under the European Union's Horizon research and innovation program, 695099 /
European Organisation for Astronomical Research in the Southern Hemisphere under ESO programs, 096.D-0425(A),
097.D-0400(A), 098.D-0263(A)