THE ARAUCARIA PROJECT: ACCURATE DETERMINATION OF THE DYNAMICAL MASS OF THE CLASSICAL CEPHEID IN THE ECLIPSING SYSTEM OGLE-LMC-CEP-1812

Journal Article · Thu Dec 15 04:00:00 EST 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/742/2/L20· OSTI ID:22047336

Pietrzynski, Grzegorz; Graczyk, Dariusz; Gieren, Wolfgang; Konorski, Piotr ^[1]; others, and

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1. Departamento de Astronomia, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile)

We have analyzed the double-lined eclipsing binary system OGLE-LMC-CEP-1812 in the LMC and demonstrate that it contains a classical fundamental mode Cepheid pulsating with a period of 1.31 days. The secondary star is a stable giant. We derive the dynamical masses for both stars with an accuracy of 1.5%, making the Cepheid in this system the second classical Cepheid with a very accurate dynamical mass determination, following the OGLE-LMC-CEP-0227 system studied by Pietrzynski et al. The measured dynamical mass agrees very well with that predicted by pulsation models. We also derive the radii of both components and accurate orbital parameters for the binary system. This new, very accurate dynamical mass for a classical Cepheid will greatly contribute to the solution of the Cepheid mass discrepancy problem, and to our understanding of the structure and evolution of classical Cepheids.

• OSTI ID: 22047336
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 742; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCURACY
ASTROPHYSICS
BINARY STARS
CEPHEIDS
DISTANCE
GALAXIES
GIANT STARS
MASS
MATHEMATICAL SOLUTIONS
PULSATIONS
RED SHIFT
STAR EVOLUTION
STAR MODELS