Hubble Tarantula Treasury Project V. The star cluster Hodge 301: the old
  face of 30 Doradus
  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 $\delta$E(B$-$V)$\approx 0.04$ mag.
