A pulsational distance to Omega Centauri based on Near-Infrared Period-Luminosity relations of RR Lyrae stars

Abstract

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.

24 pages, 7 figures, accepted for publication on The Astrophysical Journal

References in corpus (32)

• Final Results from the Hubble Space Telescope Key Project to Measure the Hubble Constant
• A large stellar evolution database for population synthesis studies. I. Scaled solar models and isochrones
• Color Transformations for the 2MASS Second Incremental Data Release
• Line formation in solar granulation: IV. [O I], OI and OH lines and the photospheric O abundance
• A large stellar evolution database for population synthesis studies. II. Stellar models and isochrones for an alpha-enhanced metal distribution
• Variable Stars in Galactic Globular Clusters
• The dynamical distance and intrinsic structure of the globular cluster omega Centauri
• The RR Lyrae Period-Luminosity Relation. I. Theoretical Calibration
• A pulsational approach to near infrared and visual magnitudes of RR Lyrae stars
• Astrometry with Hubble Space Telescope: A Parallax of the Fundamental Distance Calibrator RR Lyrae
• Cluster AgeS Experiment: The Age and Distance of the Globular Cluster omega Centauri Determined from Observations of the Eclipsing Binary OGLEGC17
• Direct Distances to Cepheids in the Large Magellanic Cloud: Evidence for a Universal Slope of the Period-Luminosity Relation up to Solar Abundance
• Cepheid Calibration of the Peak Brightness of SNe Ia. XI. SN 1998aq in NGC 3982
• RR Lyrae stars in Galactic globular clusters.III. Pulsational predictions for metal content Z=0.0001 to Z=0.006
• Globular Cluster Distances from RR Lyrae Stars
• Theoretical insights into the RR Lyrae K-band Period-Luminosity relation
• The distance to the LMC cluster Reticulum from the K-band Period-Luminosity-Metallicity relation of RR Lyrae stars
• RR Lyrae variables in Galactic globular clusters: IV. Synthetic HB and RR Lyrae predictions
• CCD Photometry of the Globular Cluster Omega Centauri. I. Metallicity of RR Lyrae Stars from Caby Photometry
• Properties of RR Lyrae stars in the Inner Regions of the Large Magellanic Cloud
• New Metallicities of RR Lyrae Stars in omega Centauri: Evidence for a Non He-Enhanced Metal-Intermediate Population
• BVI time series data of the Galactic Globular Cluster NGC3201. I. RR Lyrae stars
• Cluster AgeS Experiment. Catalog of Variable Stars in the Globular Cluster Omega Centauri
• Reddening distribution across the center of the globular cluster Omega Centauri
• On the Horizontal Branch of the Galactic Globular NGC2808
• Near-Infrared Observations of RR Lyrae variables in Galactic Globular Clusters: I. The case of M92
• Cepheid distances from infrared long-baseline interferometry - II. Calibration of the Period-Radius and Period-Luminosity relations
• IR photometric properties of Red Giants in omega Cen
• On the pulsation parallax of the variable star RR Lyr
• The RR Lyrae Star Period - K-band Luminosity Relation of the Globular Cluster M3
• The distance to IC4499 from K-band photometry of 32 RR Lyrae stars
• RR LYRAE VARIABLE STARS: PULSATIONAL CONSTRAINTS RELEVANT TO THE OOSTERHOFF CONTROVERSY

Cited by in corpus (54)

• Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy
• Clustering of Local Group distances: publication bias or correlated measurements? I. The Large Magellanic Cloud
• Improved Mass and Radius Constraints for Quiescent Neutron Stars in Omega Cen and NGC 6397
• Distance Scale Zero-Points from Galactic RR Lyrae Star Parallaxes
• The Araucaria Project. The Distance to the Sculptor dwarf spheroidal galaxy from infrared photometry of RR Lyrae stars
• Gaia Data Release 1. Testing the parallaxes with local Cepheids and RR Lyrae stars
• On the distance of the globular cluster M4 (NGC 6121) using RR Lyrae stars: I. optical and near-infrared Period-Luminosity and Period-Wesenheit relations
• Old-Aged Stellar Population Distance Indicators
• Hubble Space Telescope Observations of an Outer Field in Omega Centauri: A Definitive Helium Abundance
• Hubble Space Telescope proper motion (HSTPROMO) catalogs of Galactic globular clusters. III. Dynamical distances and mass-to-light ratios
• The VMC survey - XXVI. Structure of the Small Magellanic Cloud from RR Lyrae stars
• Discrete dynamical modelling of omega Centauri
• New near-infrared period-luminosity-metallicity relations for RR Lyrae stars and the outlook for Gaia
• The Araucaria Project. The Distance to the Small Magellanic Cloud from Near-Infrared Photometry of RR Lyrae Variables
• The non-peculiar velocity dispersion profile of the stellar system omega Centauri
• Evidence for an Overluminosity of the Variable Star RR Lyr, and a Revised Distance to the LMC
• On the RR Lyrae stars in globulars: IV. $\omega$ Centauri Optical UBVRI Photometry
• Spitzer Spectroscopy of Mass Loss and Dust Production by Evolved Stars in Globular Clusters
• A Spitzer Space Telescope Atlas of omega Centauri: The Stellar Population, Mass Loss, and the Intracluster Medium
• Ground-based CCD astrometry with wide field imagers. III. [email protected] proper-motion catalog of the globular cluster omega Centauri
• The Araucaria Project. The Distance of the Large Magellanic Cloud from Near-Infrared Photometry of RR Lyrae Variables
• Relative distances of Omega Centauri and 47 Tucanae
• Distance to Galactic globulars using the near-infrared magnitudes of RR Lyrae stars: IV. The case of M5 (NGC5904)
• Mass estimates from stellar proper motions: The mass of $\omega$ Centauri
• Star Counts in the Globular Cluster Omega Centauri. I. Bright Stellar Components
• A spectral atlas of post-main-sequence stars in omega Centauri: kinematics, evolution, enrichment and interstellar medium
• A Deep Wide-Field Variable Star Catalog of Omega Centauri
• On the distance and reddening of the starburst galaxy IC10
• On the RR Lyrae stars in globulars: V. the complete Near-Infrared (JHKs) census of omega Centauri RR Lyrae variables
• Synthetic properties of bright metal-poor variables. II. BL Her stars
• On the white dwarf cooling sequence of the globular cluster Omega Centauri
• Hot Horizontal Branch stars in omega Centauri: clues about their origin from the cluster Color Magnitude Diagram
• The VMC Survey -- XLII. Near-infrared period-luminosity relations for RR Lyrae stars and the structure of the Large Magellanic Cloud
• Characterization of the VVV Survey RR Lyrae Population across the Southern Galactic Plane
• On a new method to estimate distance, reddening and metallicity of RR Lyrae stars using optical/near-infrared ($B$,$V$,$I$,$J$,$H$,$K$) mean magnitudes: $\omega$ Centauri as a first test case
• Modeling the chemical evolution of Omega Centauri using three-dimensional hydrodynamical simulations
• Searching for tidal tails around $\omega$ Centauri using RR Lyrae Stars
• On the period distribution of cluster RR Lyrae stars to constrain their helium content: the case of omega Centauri
• Bulge RR Lyrae stars in the VVV tile $\text{b201}$
• An Updated Census of RR~Lyrae Stars in the Globular Cluster $\omega$~Centauri (NGC\,5139)
• MgAl burning chain in Omega Centauri
• Blue straggler masses from pulsation properties. II. Topology of the Instability Strip
• On the absolute age of the metal-rich globular M71 (NGC 6838): I. optical photometry
• On the variation of light curve parameters of RR Lyrae variables at multiple wavelengths
• STREGA: STRucture and Evolution of the GAlaxy. I. Survey Overview and First Results
• Near-IR period-luminosity relations for pulsating stars in $\omega$ Centauri (NGC 5139)
• The Mg-K anti-correlation in Omega Centauri
• Revisiting Delta Y/Delta Z from multiple main sequences in Globular Clusters: insight from nearby stars
• Discovery of a rapidly pulsating subdwarf B star candidate in omega Cen
• Impact of distance determinations on Galactic structure. II. Old tracers
• A Search for Annihilating Dark Matter in 47 Tucanae and Omega Centauri
• Just how hot are the $\omega$ Centauri extreme horizontal branch pulsators?
• Variable stars in the VVV globular clusters. II. NGC6441, NGC6569, NGC6626 (M28), NGC6656 (M22), 2MASS-GC02, and Terzan10
• MAD@VLT: Deep into the Madding Crowd of Omega Centauri