The Carnegie RR Lyrae Program: mid-infrared period–luminosity relations of RR Lyrae stars in Reticulum

We analysed 30 RR Lyrae stars (RRLs) located in the Large Magellanic Cloud (LMC) globular cluster Reticulum that were observed in the 3.6 and 4.5 $\mu$m passbands with the Infrared Array Camera (IRAC) on board of the Spitzer Space Telescope. We derived new mid-infrared (MIR) period-luminosity PL relations. The zero points of the PL relations were estimated using the trigonometric parallaxes of five bright Milky Way (MW) RRLs measured with the Hubble Space Telescope (HST) and, as an alternative, we used the trigonometric parallaxes published in the first Gaia data release (DR1) which were obtained as part of the Tycho-Gaia Astrometric Solution (TGAS) and the parallaxes of the same stars released with the second Gaia data release (DR2). We determined the distance to Reticulum using our new MIR PL relations and found that distances calibrated on the TGAS and DR2 parallaxes are in a good agreement and, generally, smaller than distances based on the HST parallaxes, although they are still consistent within the respective errors. We conclude that Reticulum is located ~3 kpc closer to us than the barycentre of the LMC.

[1]  Jean-Luc Starck,et al.  Astronomical Data Analysis , 2007 .

[2]  H. Schmitt,et al.  A Revised and Extended Catalog of Magellanic System Clusters, Associations, and Emission Nebulae. II. The Large Magellanic Cloud , 1998, astro-ph/9810266.

[3]  M. Dall'Ora,et al.  ON THE DISTANCE OF THE GLOBULAR CLUSTER M4 (NGC 6121) USING RR LYRAE STARS. II. MID-INFRARED PERIOD–LUMINOSITY RELATIONS , 2015, 1505.07858.

[4]  Massimo Marengo,et al.  On a New Theoretical Framework for RR Lyrae Stars. II. Mid-infrared Period–Luminosity–Metallicity Relations , 2017, 1705.01970.

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

[6]  Wendy L. Freedman,et al.  Standard Galactic Field RR Lyrae. I. Optical to Mid-infrared Phased Photometry , 2017, 1703.01520.

[7]  L. M. Sarro,et al.  Gaia Data Release 2 , 2018, Astronomy & Astrophysics.

[8]  H. E. Delgado,et al.  RR Lyrae stars as standard candles in the Gaia Data Release 2 Era , 2018, Monthly Notices of the Royal Astronomical Society.

[9]  C. Barache,et al.  Gaia Data Release 2 , 2018, Astronomy & Astrophysics.

[10]  T. A. Lister,et al.  Gaia Data Release 2. Summary of the contents and survey properties , 2018, 1804.09365.

[11]  A. Heck,et al.  Post-Hipparcos cosmic candles , 1999 .

[12]  Thomas E. Lutz,et al.  ON THE USE OF TRIGONOMETRIC PARALLAXES FOR THE CALIBRATION OF LUMINOSITY SYSTEMS: THEORY , 1973 .

[13]  Daniel Egret,et al.  Harmonizing Cosmic Distance Scales in a Post‐Hipparcos Era , 1999 .

[14]  S. E. Persson,et al.  THE CARNEGIE HUBBLE PROGRAM: THE LEAVITT LAW AT 3.6 AND 4.5 μm IN THE MILKY WAY , 2012, 1209.4946.

[15]  Carnegie Observatories,et al.  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 , 2014, 1411.6826.

[16]  Tatiana Muraveva,et al.  NEW NEAR-INFRARED PERIOD–LUMINOSITY–METALLICITY RELATIONS FOR RR LYRAE STARS AND THE OUTLOOK FOR GAIA , 2015, 1505.06001.

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

[18]  V. Ripepi,et al.  Pulsational MV versus [Fe/H] relation(s) for globular cluster RR Lyrae variables , 2000, astro-ph/0003473.

[19]  Observatoire de la Côte d'Azur,et al.  Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties , 2016, 1609.04172.

[20]  Wendy L. Freedman,et al.  THE CARNEGIE HUBBLE PROGRAM , 2011, 1109.3802.

[21]  Robert Mann,et al.  Astronomical Data Analysis Software and Systems XXI , 2012 .

[22]  European Southern Observatory,et al.  On the RR Lyrae Stars in Globulars. V. The Complete Near-infrared (JHKs) Census of ω Centauri RR Lyrae Variables , 2018, 1802.03578.

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

[24]  A. Walker,et al.  B, V PHOTOMETRY FOR ∼19,000 STARS IN AND AROUND THE MAGELLANIC CLOUD GLOBULAR CLUSTERS NGC 1466, NGC 1841, NGC 2210, NGC 2257, AND RETICULUM , 2014 .

[25]  C. Barache,et al.  Gaia Data Release 1: Astrometry - one billion positions, two million proper motions and parallaxes , 2016, 1609.04303.

[26]  Wendy L. Freedman,et al.  A PRELIMINARY CALIBRATION OF THE RR LYRAE PERIOD–LUMINOSITY RELATION AT MID-INFRARED WAVELENGTHS: WISE DATA , 2013, 1308.3160.

[27]  A. Mackey,et al.  Comparing the properties of local globular cluster systems: implications for the formation of the Galactic halo , 2004, astro-ph/0408404.

[28]  G. Fazio,et al.  The Infrared Array Camera (IRAC) for the Spitzer Space Telescope , 2004, astro-ph/0405616.

[29]  Nathaniel R. Butler,et al.  Mid-infrared period–luminosity relations of RR Lyrae stars derived from the AllWISE Data Release , 2014, 1402.4449.

[30]  Bias in absolute magnitude determination from parallaxes , 2002, astro-ph/0208537.

[31]  J. Zinn,et al.  Confirmation of the Gaia DR2 Parallax Zero-point Offset Using Asteroseismology and Spectroscopy in the Kepler Field , 2018, The Astrophysical Journal.

[32]  M. Cropper,et al.  Gaia Data Release 2 , 2018, Astronomy & Astrophysics.

[33]  N. Mowlavi,et al.  Gaia Data Release 2 , 2018, Astronomy & Astrophysics.

[34]  M. Feast,et al.  The Cepheid period-luminosity zero-point from Hipparcos trigonometrical parallaxes† , 1997 .

[35]  Michael J. West,et al.  The globular cluster system of the Galaxy. III: measurements of radial velocity and metallicity for 60 clusters and a compilation of metallicities for 121 clusters , 1984 .

[36]  Soo-Chang Rey,et al.  CCD Photometry of the Globular Cluster ω Centauri. I. Metallicity of RR Lyrae Stars from Caby Photometry , 2000 .

[37]  B. Madore,et al.  MULTI-WAVELENGTH CHARACTERISTICS OF PERIOD–LUMINOSITY RELATIONS , 2011, 1111.6313.

[38]  F. V. Leeuwen,et al.  Hipparcos, the New Reduction of the Raw Data , 2007 .

[39]  A. Dambis,et al.  Mid-infrared period-luminosity relations for globular cluster RR Lyrae , 2014, 1401.5523.

[40]  V. M. Larionov,et al.  The infrared JHK light curves of RR Lyr , 2007, 0712.0578.

[41]  D. Schlegel,et al.  Maps of Dust Infrared Emission for Use in Estimation of Reddening and Cosmic Microwave Background Radiation Foregrounds , 1998 .

[42]  R. Kudritzki,et al.  An eclipsing-binary distance to the Large Magellanic Cloud accurate to two per cent , 2013, Nature.

[43]  The Wavelength Dependence of Interstellar Extinction from 1.25 to 8.0 μm Using GLIMPSE Data , 2004, astro-ph/0406403.

[44]  Paul M. Brunet,et al.  The Gaia mission , 2013, 1303.0303.

[45]  Nicole Nesvacil,et al.  DISTANCE SCALE ZERO POINTS FROM GALACTIC RR LYRAE STAR PARALLAXES , 2011, 1109.5631.

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

[47]  University of Sydney,et al.  VARIABLE STARS IN LARGE MAGELLANIC CLOUD GLOBULAR CLUSTERS. III. RETICULUM , 2013, 1307.6644.

[48]  Peter B. Stetson,et al.  THE CENTER OF THE CORE-CUSP GLOBULAR CLUSTER M15: CFHT AND HST OBSERVATIONS, ALLFRAME REDUCTIONS , 1994 .

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

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

[51]  Richard de Grijs,et al.  CLUSTERING OF LOCAL GROUP DISTANCES: PUBLICATION BIAS OR CORRELATED MEASUREMENTS? III. THE SMALL MAGELLANIC CLOUD , 2014, 1504.00417.

[52]  L. Szabados,et al.  Gaia Data Release 1. Testing parallaxes with local Cepheids and RR Lyrae stars , 2017, 1705.00688.

[53]  G. Bono,et al.  CLUSTERING OF LOCAL GROUP DISTANCES: PUBLICATION BIAS OR CORRELATED MEASUREMENTS? I. THE LARGE MAGELLANIC CLOUD , 2014, 1403.3141.

[54]  Stefano Casertano,et al.  Milky Way Cepheid Standards for Measuring Cosmic Distances and Application to Gaia DR2: Implications for the Hubble Constant , 2018, The Astrophysical Journal.

[55]  A. Pietrinferni,et al.  ON A NEW THEORETICAL FRAMEWORK FOR RR LYRAE STARS. I. THE METALLICITY DEPENDENCE , 2015, 1505.02531.

[56]  CU Comae: A New Field Double-Mode RR Lyrae Variable, the Most Metal-poor Discovered to Date , 2000, astro-ph/0006174.

[57]  E. Grebel,et al.  Old and New Tools for Understanding the Evolution of Stars in Clusters , 2001 .

[58]  C. Sturch.  Intrinsic UBV colors of RR Lyrae stars , 1966 .

[59]  G. Bono,et al.  Theoretical insights into the RR Lyrae K-band period–luminosity relation , 2001 .

[60]  H. Rix,et al.  The >100 kpc Distant Spur of the Sagittarius Stream and the Outer Virgo Overdensity, as Seen in PS1 RR Lyrae Stars , 2017, 1706.10187.

[61]  A. Walker.  The LMC cluster NGC 1466 - Photometry of the RR Lyraes, and a color-magnitude diagram , 1990 .

[62]  K. Stassun,et al.  Evidence for a Systematic Offset of −80 μas in the Gaia DR2 Parallaxes , 2018, The Astrophysical Journal.

[63]  Massimo Marengo,et al.  SMHASH: anatomy of the Orphan Stream using RR Lyrae stars , 2017, Monthly Notices of the Royal Astronomical Society.

[64]  E. Wright,et al.  The Spitzer Space Telescope Mission , 2004, astro-ph/0406223.

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

[66]  P. Stetson.  DAOPHOT: A COMPUTER PROGRAM FOR CROWDED-FIELD STELLAR PHOTOMETRY , 1987 .

[67]  J. P. Huchra,et al.  Final Results from the Hubble Space Telescope Key Project to Measure the Hubble Constant , 1998, astro-ph/9801080.

[68]  J. J. González-Vidal,et al.  Gaia Data Release 2 , 2018, Astronomy & Astrophysics.

[69]  B. Chaboyer.  GLOBULAR CLUSTER DISTANCE DETERMINATIONS , 1998, astro-ph/9808202.

[70]  Gaia Collaboration,et al.  The Gaia mission , 2016, 1609.04153.