The infrared JHK light curves of RR Lyr

We present infrared JHK time series photometry of the variable star RR Lyr, that allows us to construct the first complete and accurate infrared light curves for this star. The derived mean magnitudes areJ �= 6.74 ± 0.02, � H �= 6.60 ± 0.03 andK �= 6.50 ± 0.02. TheK� magnitude is used to estimate the reddening, the mass, the mean luminosity and the temperature of this variable star. The use of these RR Lyr data provides a more accurate absolute calibration of the P-LK-(Fe/H) relation, and a distance modulus (m − M)0 = 18.48 ± 0.11 to the globular cluster Reticulum in the Large Magellanic Cloud.

[1]  M. Dolci,et al.  Near-Infrared Observations of RR Lyrae Variables in Galactic Globular Clusters. I. The Case of M92 , 2005, astro-ph/0503140.

[2]  V. Blanco.  The reddening of Type AB RR Lyrae Stars , 1992 .

[3]  M. Catelan,et al.  The RR Lyrae Period-Luminosity Relation. I. Theoretical Calibration , 2004, astro-ph/0406067.

[4]  T. D. Wilson,et al.  Observational studies of Cepheids. VIII - Additional radial velocities of Cepheids and RR Lyrae variables , 1989 .

[5]  F. V. Leeuwen.  Validation of the new Hipparcos reduction , 2007, 0708.1752.

[6]  S. Degl'Innocenti,et al.  A pulsational approach to near-infrared and visual magnitudes of RR Lyr stars , 2003 .

[7]  E. Bertin,et al.  SExtractor: Software for source extraction , 1996 .

[8]  P. Gay,et al.  The Blazhko Effect of RR Lyrae in 1996 , 2003 .

[9]  S. E. Persson,et al.  New Cepheid Period-Luminosity Relations for the Large Magellanic Cloud: 92 Near-Infrared Light Curves , 2004 .

[10]  C. D. Laney,et al.  Cepheid parallaxes and the Hubble constant , 2007, 0705.1592.

[11]  R. G. Gratton,et al.  Abundances for globular cluster giants: I. homogeneous metallicities for 24 clusters , 1996, astro-ph/9607078.

[12]  Towards the absolute planes: a new calibration of the bolometric corrections and temperature scales for Population II giants , 1998, astro-ph/9804297.

[13]  A. Walker.  The LMC cluster GLC 0435-59 (Reticulum) : photometry of the RR Lyraes, and a color-magnitude diagram , 1992 .

[14]  K. Cook,et al.  Properties of RR Lyrae stars in the inner regions of the Large Magellanic Cloud , 2004 .

[15]  W. Jefferys,et al.  Astrometry with the Hubble Space Telescope: A Parallax of the Fundamental Distance Calibrator RR Lyrae , 2001, astro-ph/0110271.

[16]  A. Walker,et al.  Spectroscopy of Giants in LMC Clusters. III. Velocities and Abundances for NGC 1841 and Reticulum and the Properties of the Metal-Poor Clusters , 1992 .

[17]  A Multicolor and Fourier Study of RR Lyrae Variables in the Globular Cluster NGC 5272 (M3) , 2004, astro-ph/0409567.

[18]  Bruce W. Carney,et al.  TEMPLATE K LIGHT CURVES FOR RR LYRAE STARS , 1996 .

[19]  B. Paczyński,et al.  Atmospheric Phenomena in the RR Lyrae Stars. II. The 41-DAY Cycle of RR Lyrae. , 1965 .

[20]  C. Heiles,et al.  H I, galaxy counts, and reddening: Variation in the gas-to-dust ratio, the extinction at high galactic latitudes, and a new method for determining galactic reddening , 1978 .

[21]  A. Bragaglia,et al.  Distance to the Large Magellanic Cloud: The RR Lyrae Stars* , 2000 .

[22]  W. Gieren,et al.  Direct Distances to Cepheids in the Large Magellanic Cloud: Evidence for a Universal Slope of the Period-Luminosity Relation up to Solar Abundance , 2005, astro-ph/0503637.

[23]  M. Bessell,et al.  JHKLM PHOTOMETRY: STANDARD SYSTEMS, PASSBANDS, AND INTRINSIC COLORS , 1988 .

[24]  Santiago Arribas,et al.  The effective temperature scale of giant stars (F0–K5) - II. Empirical calibration of versus colours and [Fe/H] , 1999 .

[25]  E. Valenti,et al.  The RR Lyrae period–K-luminosity relation for globular clusters: an observational approach★ , 2006, astro-ph/0608397.

[26]  J. Mathis,et al.  The relationship between infrared, optical, and ultraviolet extinction , 1989 .

[27]  R. Merighi,et al.  The Composition of HB Stars: RR Lyrae Variables , 1995 .

[28]  D. Alexander,et al.  Models for Old, Metal-poor Stars with Enhanced α-Element Abundances. I. Evolutionary Tracks and ZAHB Loci; Observational Constraints , 2000 .

[29]  J. Carpenter.  Color Transformations for the 2MASS Second Incremental Data Release , 2001, astro-ph/0101463.

[30]  V. Ripepi,et al.  The distance to the LMC cluster Reticulum from the K-band Period-Luminosity-Metallicity relation of RR Lyrae stars , 2004 .

[31]  K. Kolenberg,et al.  The Blazhko effect of RR lyrae in 2003-2004 , 2006 .

[32]  R. Stellingwerf,et al.  Synthetic Mean Colors for RR Lyrae Variables , 1995 .