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arXiv · 1610.06180

Hubble Tarantula Treasury Project V. The star cluster Hodge 301: the old face of 30 Doradus

M. Cignoni·E. Sabbi·R. P. van der Marel·D. J. Lennon·M. Tosi·E. K. Grebel·J. S. Gallagher·A. Aloisi·G. de Marchi·D. A. Gouliermis·S. Larsen·N. Panagia·L. J. Smith
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Abstract

Based on color-magnitude diagrams (CMDs) from the Hubble Space Telescope Hubble Tarantula Treasury Project (HTTP) survey, we present the star formation history (SFH) of Hodge~301, the oldest star cluster in the Tarantula Nebula. The HTTP photometry extends faint enough to reach, for the first time, the cluster pre-main sequence (PMS) turn-on, where the PMS joins the main sequence. Using the location of this feature, along with synthetic CMDs generated with the latest PARSEC models, we find that Hodge~301 is older than previously thought, with an age between 26.5 and 31.5 Myr. From this age, we also estimate that between 38 and 61 supernovae Type-II exploded in the region. The same age is derived from the main sequence turn-off, whereas the age derived from the post-main sequence stars is younger and between 20 and 25 Myr. Other relevant parameters are a total stellar mass of $\approx 8800\,\pm 800$M$_{\odot}$ and average reddening E(B$-$V) $\approx 0.22-0.24$ mag, with a differential reddening $δ$E(B$-$V)$\approx 0.04$ mag.

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M. Cignoni, E. Sabbi, R. P. van der Marel, D. J. Lennon, M. Tosi, E. K. Grebel, J. S. Gallagher, A. Aloisi, G. de Marchi, D. A. Gouliermis, S. Larsen, N. Panagia, L. J. Smith. 2016-10-19. Hubble Tarantula Treasury Project V. The star cluster Hodge 301: the old face of 30 Doradus. https://doi.org/10.3847/1538-4357%2F833%2F2%2F154

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