J/MNRAS/439/3765 RR Lyrae in 15 Galactic globular clusters (Dambis+, 2014) ================================================================================ Mid-infrared period-luminosity relations for globular cluster RR Lyrae. Dambis A.K., Rastorguev A.S., Zabolotskikh M.V. =2014MNRAS.439.3765D ================================================================================ ADC_Keywords: Clusters, globular ; Stars, variable ; Photometry, infrared Keywords: stars: distances - stars: variables: RR Lyrae - globular clusters: general - infrared: stars Abstract: The period-metallicity-WISE W1- and W2-band luminosity relations are derived for RR Lyrae stars based on WISE epoch photometry for 360 and 275 stars in 15 and 9 Galactic globular clusters, respectively. Our final relations have the form ={gamma}_W1-(2.381+/-0.097)logP_F_+(0.096+/-0.021)[Fe/H] and ={gamma}_W2_-(2.269+/-0.127)logP_F_+(0.108+/-0.021)[Fe/H], where [Fe/H] values are on the scale of Carretta et al. (2009A&A...508..695C). We obtained two appreciably discrepant estimates for the zero-points {gamma}_W1_ and {gamma}_W2_ of both relations: one based on a statistical-parallax analysis - {gamma}_W1_=-0.829+/-0.093 and {gamma}_W2_=-0.776+/-0.093 and another, significantly brighter one, based on Hubble Space Telescope (HST) Fine Guidance Sensor (FGS) trigonometric parallaxes - {gamma}_W1,HST_=-1.150+/-0.077 and {gamma}_W2,HST_=-1.105+/-0.077. The period-metallicity-luminosity relations in the two bands yield highly consistent distance moduli for the calibrator clusters and the distance moduli computed using the W1- and W2-band relations with the HST zero-points agree well with those computed by Sollima, Cacciari & Valenti based on their derived period-metallicity-K-band luminosity relation whose zero-point is tied to the HST trigonometric parallax of RR Lyrae itself ({Delta}DM0 =0.04 and 0.06, respectively, with a scatter of only 0.06). Description: Last year, the WISE All-Sky Data Release (Cutri et al., 2012, Cat. II/328) was made public, mapping the entire sky in four mid-infrared bands W1, W2, W3 and W4 with the effective wavelengths of 3.368, 4.618, 12.082 and 22.194um, respectively. We cross-correlated the WISE single-exposure data base with the Catalogue of Galactic globular-cluster variables by Clement et al. (2001AJ....122.2587C), the Catalogue of Accurate Equatorial Coordinates for Variable Stars in Globular Clusters by Samus et al. (2009PASP..121.1378S, Cat. J/PASP/121/1378) and the catalogue of Sawyer Hogg (1973PDDO....3....6S, Cat. V/97) (for {omega} Cen, NGC 6723 and NGC 6934) to compute (via Fourier fits) the intensity-mean average W1- and W2-band magnitudes, and , for a total of 357 and 272 RR Lyrae type variables in 15 and 9 Galactic globular clusters, respectively. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 73 360 The data for RR Lyraes in the calibrator GCs -------------------------------------------------------------------------------- See also: II/328 : AllWISE Data Release (Cutri+ 2013) V/97 : Updated 3rd Cat Variable Stars in Globular Clusters (Clement+ 1997) J/PASP/121/1378 : Positions of variable stars in globular clusters (Samus+, 2009) Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 7 A7 --- Cluster Cluster name (NGCNNNN) 10- 18 A9 --- AName Alternative cluster name 20- 23 A4 --- Var Variable designation within the cluster (VNNN) 25- 32 F8.6 d Per Period 34- 40 F7.4 mag WISE W1-band intensity-mean magnitude 42- 47 F6.4 mag e_ rms uncertainty on 50- 56 F7.4 mag WISE W2-band intensity-mean magnitude 58- 63 F6.4 mag e_ rms uncertainty on 67- 69 A3 --- Type RR Lyr type: RR0=RRab, RR1=RRc(first overtone), RR2=RRd (double mode), RR9=unknown subtype 73 I1 --- Use [0/1] Used (1) or rejected (0) in the final Period-Luminosity relation fit -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Patricia Vannier [CDS] 20-Dec-2014