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arXiv · 1308.3160

A Preliminary Calibration of the RR Lyrae Period-Luminosity Relation at Mid-Infrared Wavelengths: WISE Data

Barry F. Madore·Douglas Hoffman·Wendy L. Freedman·Juna A. Kollmeier·Andy Monson·S. Eric Persson·Jeff A. Rich Jr.·Victoria Scowcroft·Mark Seibert
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Abstract

Using time-resolved, mid-infrared data from WISE and geometric parallaxes from HST for four Galactic RR Lyrae variables, we derive the following Population II Period-Luminosity (PL) relations for the WISE [W1], [W2] and [W3] bands at 3.4, 4.6 & 12 um, respectively: M[W1] = -2.44 (+/- 0.95) x logP - 1.26 (+/- 0.25) sigma = 0.10 M[W2] = -2.55 (+/- 0.89) x logP - 1.29 (+/- 0.23) sigma = 0.10 M[W3] = -2.58 (+/- 0.97) x logP - 1.32 (+/- 0.25) sigma = 0.10 The slopes and the scatter around the fits are consistent with a smooth extrapolation of those same quantities from previously-published K-band observations at 2.2 um, where the asymptotic (long-wavelength) behavior is consistent with a Period-Radius relation having a slope of 0.5. No obvious correlation with metallicity (spanning 0.4 dex in [Fe/H]) is found in the residuals of the four calibrating RR Lyrae stars about the mean PL regression line.

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Barry F. Madore, Douglas Hoffman, Wendy L. Freedman, Juna A. Kollmeier, Andy Monson, S. Eric Persson, Jeff A. Rich Jr., Victoria Scowcroft, Mark Seibert. 2013-08-14. A Preliminary Calibration of the RR Lyrae Period-Luminosity Relation at Mid-Infrared Wavelengths: WISE Data. https://doi.org/10.1088/0004-637x%2F776%2F2%2F135

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