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Near-Infrared Observations of RR Lyrae Variables in $ω$ Centauri

M. Del Principe·A. M. Piersimoni·J. Storm·G. Bono·F. Caputo·S. Cassisi·L. M. Freyhammer·M. Marconi·P. B. Stetson
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Abstract

We present Near-Infrared (NIR) $J$ and $K_s$-band observations for 181 RR Lyrae stars in the Galactic Globular Cluster $ω$ Cen. The comparison between predicted and empirical slopes of NIR Period-Luminosity (PL) relations indicates a very good agreement. Cluster distance estimates based on NIR PL relations agree quite well with recent determinations based on different standard candles, giving a true mean distance modulus $μ= 13.71\pm0.05$, and $d=5.52\pm0.13$ kpc.

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M. Del Principe, A. M. Piersimoni, J. Storm, G. Bono, F. Caputo, S. Cassisi, L. M. Freyhammer, M. Marconi, P. B. Stetson. 2005-10-06. Near-Infrared Observations of RR Lyrae Variables in $ω$ Centauri. https://arxiv.org/abs/astro-ph/0510174

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