2010/11/01 by G. Pietrzynski, G. Pietrzyński, I. B. Thompson +9 · 138 citations
Mathematics · Physics and Astronomy · #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Binary number #Binary star #Cepheid variable #Mathematical analysis #Mathematics #Physics #Star (game theory) #Stars #Stellar, planetary, and galactic studies #Variable (mathematics) #astro-ph.GA
paper · pdf · doi:10.1038/nature09598
published in Nature 468(7323), 542-544 (Nature Portfolio) · Nature, 468, 542
openalex publication_date 2010/11/01 · arxiv created 2010/12/01 · arxiv updated 2018/12/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Stellar pulsation theory provides a means of determining the masses of pulsating classical Cepheid supergiant - it is the pulsation that causes their luminosity to vary. Such pulsational masses are found to be smaller than the masses derived from stellar evolution theory: this is the Cepheid mass discrepancy problem, for which a solution is missing. An independent, accurate dynamical mass determination for a classical Cepheid variable star (as opposed to type-II Cepheids, low-mass stars with a very different evolutionary history) in a binary system is needed in order to determine which is correct. The accuracy of previous efforts to establish a dynamical Cepheid mass from Galactic single-lined noneclipsing binaries was typically about 15-30 per cent, which is not good enough to resolve the mass discrepancy problem. In spite of many observational efforts, no firm detection of a classical Cepheid in an eclipsing double-lined binary has hitherto been reported. Here we report the discovery of a classical Cepheid in a well detached, double-lined eclipsing binary in the Large Magellanic Cloud. We determine the mass to a precision of one per cent and show that it agrees with its pulsation mass, providing strong evidence that pulsation theory correctly and precisely predicts the masses of classical Cepheids