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Near-Infrared photometry of LMC cluster Reticulum

M. Dall'Ora·G. Bono·J. Storm·V. Testa·G. Andreuzzi·R. Buonanno·F. Caputo·V. Castellani·C. E. Corsi·S. Degl'Innocenti·G. Marconi·M. Marconi·M. Monelli·V. Ripepi
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Abstract

We present near-infrared (JKs) time series data of the Large Magellanic Cloud (LMC) cluster Reticulum. The observing strategy and data reduction (DAOPHOTII/ALLFRAME) allowed us to reach a photometry accuracy of the order of 0.02 mag at limiting magnitudes typical of RR Lyrae stars. We are interested in Reticulum, since it hosts a sizable sample of RR Lyrae (32), and therefore the use of the K-band Period-Luminosity-Metallicity (PLZ_K) relation will allow us to supply an accurate LMC distance evaluation. The main advantages in using this method is that it is marginally affected by off-ZAHB evolutionary effects and by reddening corrections. As a preliminary but robust result we find a true distance in good agreement with the LMC Cepheid distance scale, i.e. DM = 18.47 +- 0.07 mag.

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M. Dall'Ora, G. Bono, J. Storm, V. Testa, G. Andreuzzi, R. Buonanno, F. Caputo, V. Castellani, C. E. Corsi, S. Degl'Innocenti, G. Marconi, M. Marconi, M. Monelli, V. Ripepi. 2003-05-15. Near-Infrared photometry of LMC cluster Reticulum. https://arxiv.org/abs/astro-ph/0305276

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