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The Carina Project: II. Stellar Populations

M. Monelli·L. Pulone·C. E. Corsi·M. Castellani·G. Bono·A. R. Walker·E. Brocato·R. Buonanno·F. Caputo·V. Castellani·M. Dall'Ora·M. Marconi·M. Nonino·V. Ripepi·H. A. Smith
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Abstract

We present a new (V,B-V) Color-Magnitude Diagram (CMD) of the Carina dwarf spheroidal (dSph) that extends from the tip of the Red Giant Branch (RGB) down to about V=25 mag. Data were collected with the Wide Field Imager (WFI) available at 2.2m ESO/MPI telescope and cover an area of about 0.3 square degrees around the center of the galaxy. We confirm the occurrence of a substantial amount of old stars with ages around 11 Gyr, together with an intermediate-age population around 5 Gyr. Moreover, we also detected a new well-defined blue plume of young Main-Sequence (MS) stars with an age at most of the order of 1 Gyr. At odds with previous results available in the literature we found thatstars along the RGB of the old and of the intermediate-age stellar populationindicate a mean metallicity roughly equal to Z=0.0004 and a small dispersion around this value. We find evidence for a smooth spatial distribution of the "intermediate-age" stellar population, which appears more centrally concentrated than the oldest one.

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M. Monelli, L. Pulone, C. E. Corsi, M. Castellani, G. Bono, A. R. Walker, E. Brocato, R. Buonanno, F. Caputo, V. Castellani, M. Dall'Ora, M. Marconi, M. Nonino, V. Ripepi, H. A. Smith. 2003-03-21. The Carina Project: II. Stellar Populations. https://doi.org/10.1086/375457

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