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arXiv · 0804.0347

The Araucaria Project. The Distance to the Sculptor dwarf spheroidal galaxy from infrared photometry of RR Lyrae stars

G. Pietrzynski·W. Gieren·O. Szewczyk·A. Walker·L. Rizzi·F. Bresolin·R. -P. Kudritzki·K. Nalewajko·J. Storm·M. Dall'Ora·V. Ivanov
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Abstract

We have obtained single-phase near-infrared magnitudes in the J and K bands for a sample of 78 RR Lyrae stars in the Sculptor dSph galaxy. Applying different theoretical and empirical calibrations of the period-luminosity-metallicity relation for RR Lyrae stars in the infrared, we find consistent results and obtain a true, reddening-corrected distance modulus of 19.67 $\pm$ 0.02 (statistical) $\pm$ 0.12 (systematic) mag for Sculptor from our data. This distance value is consistent with the value of 19.68 $\pm$ 0.08 mag which we obtain from earlier V-band data of RR Lyrae stars in Sculptor, and the V magnitude-metallicity calibration of Sandage (1993). It is also in a very good agreement with the results obtain by Rizzi (2002) based on tip of the red giant branch (TRGB, 19.64 $\pm$ 0.08 mag) and horizontal branch (HB, 19.66 $\pm$ 0.15 mag).

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G. Pietrzynski, W. Gieren, O. Szewczyk, A. Walker, L. Rizzi, F. Bresolin, R. -P. Kudritzki, K. Nalewajko, J. Storm, M. Dall'Ora, V. Ivanov. 2008-04-02. The Araucaria Project. The Distance to the Sculptor dwarf spheroidal galaxy from infrared photometry of RR Lyrae stars. https://doi.org/10.1088/0004-6256%2F135%2F6%2F1993

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