A Pulsational Distance to ω Centauri Based on Near‐Infrared Period‐Luminosity Relations of RR Lyrae Stars
العنوان: | A Pulsational Distance to ω Centauri Based on Near‐Infrared Period‐Luminosity Relations of RR Lyrae Stars |
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المؤلفون: | M. Del Principe, P. B. Stetson, Massimo Dall'Ora, R. Buonanno, I. Ferraro, Jesper Storm, Mario Nonino, M. Monelli, Annalisa Calamida, G. Iannicola, L. M. Freyhammer, A. M. Piersimoni, Giuseppe Bono, C. E. Corsi, V. Ripepi, L. Pulone, Marco Castellani, Filippina Caputo |
المصدر: | The Astrophysical Journal. 652:362-369 |
بيانات النشر: | American Astronomical Society, 2006. |
سنة النشر: | 2006 |
مصطلحات موضوعية: | FOS: Physical sciences, Photometric system, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Globular clusters: individual (ω Centauri), RR Lyrae variable, Luminosity, Settore FIS/05 - Astronomia e Astrofisica, Stars: oscillations, Astrophysics::Solar and Stellar Astrophysics, Omega Centauri, Astrophysics::Galaxy Astrophysics, Physics, Distance scale, Astrophysics (astro-ph), Astronomy and Astrophysics, Horizontal branch, Stars: evolution, Distance modulus, Stars, Stars: variables: other, Space and Planetary Science, Stars: horizontal-branch, Globular cluster, Astrophysics::Earth and Planetary Astrophysics |
الوصف: | We present new Near-Infrared (J,K) magnitudes for 114 RR Lyrae stars in the globular cluster Omega Cen (NGC 5139) which we combine with data from the literature to construct a sample of 180 RR Lyrae stars with J and K mean magnitudes on a common photometric system. This is presently the largest such sample in any stellar system. We also present updated predictions for J,K-band Period-Luminosity relations for both fundamental and first-overtone RR Lyrae stars, based on synthetic horizontal branch models with metal abundance ranging from Z=0.0001 to Z=0.004. By adopting for the Omega Cen variables with measured metal abundances an alpha-element enhancement of a factor of 3 (about 0.5 dex) with respect to iron we find a true distance modulus of 13.70 (with a random error of 0.06 and a systematic error of 0.06), corresponding to a distance d=5.5 Kpc (with both random and systematic errors equal to 0.03 Kpc). Our estimate is in excellent agreement with the distance inferred for the eclipsing binary OGLEGC-17, but differ significantly from the recent distance estimates based on cluster dynamics and on high amplitude Delta Scuti stars. Comment: 24 pages, 7 figures, accepted for publication on The Astrophysical Journal |
تدمد: | 1538-4357 0004-637X |
الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::50c3ad0d646747eef93ed2d90906ac67Test https://doi.org/10.1086/508136Test |
حقوق: | OPEN |
رقم الانضمام: | edsair.doi.dedup.....50c3ad0d646747eef93ed2d90906ac67 |
قاعدة البيانات: | OpenAIRE |
تدمد: | 15384357 0004637X |
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