Mid-infrared period-luminosity relations of RR Lyrae stars derived from the AllWISE Data Release

Abstract

We use photometry from the recent AllWISE Data Release of the Wide-field Infrared Survey Explorer (WISE) of 129 calibration stars, combined with prior distances obtained from the established MV-[Fe/H] relation and Hubble Space Telescope trigonometric parallax, to derive mid-infrared period-luminosity relations for RR Lyrae pulsating variable stars. We derive relations in the W1, W2 and W3 wavebands (3.4, 4.6 and 12 μm, respectively), and for each of the two mainRRLyrae sub-types (RRab and RRc).We report an error on the period-luminosity relation slope for RRab stars of 0.2.We also fit posterior distances for the calibration catalogue and find a median fractional distance error of 0.8 per cent. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.