Star clusters and young populations in the dwarf irregular galaxy Leo A
  We have studied young stellar populations and star clusters in the dwarf
irregular galaxy Leo A using multicolor ($B$, $V$, $R$, $I$, $H\alpha$)
photometry data obtained with the Subaru Suprime-Cam and two-color photometry
results measured on archival HST/ACS $F475W$ and $F814W$ frames. The analysis
of the main sequence (MS) and blue supergiant (BSG - "blue loop") stars enabled
us to study the star formation history in the Leo A galaxy during the last
$\sim$200 Myr. Also, we have discovered 5 low-mass ($\lesssim$400 M$_\odot$)
star clusters within the ACS field. This finding, taking into account a low
metallicity environment and a yet-undetected molecular gas in Leo A, constrains
star formation efficiency estimates and scenarios. Inside the well known "hole"
in the HI column density map (Hunter et al. 2012) we found a shock front
(prominent in $H\alpha$), implying an unseen progenitor and reminding the
"hole" problems widely discussed by Warren et al. (2011).
