Bright-red stars in the dwarf irregular galaxy Leo A

We analysed a population of bright-red (BR) stars in the dwarf irregular galaxy Leo A by using multicolour photometry data obtained with the Subaru/Suprime-Cam (B, V, R, I,Hα) and HST/ACS (F475W & F814W) instruments. In order to separate the Milky Way (MW) and Leo A populations of red stars, we developed a photometric method, which enabled us to study the spatial distribution of BR stars within the Leo A galaxy.

We found a significant difference in the scale-length (S-L) of radial distributions of the ``young'' and ``old'' red giant branch (RGB) stars - 0'.82 +/- 0'.04 and 1'53 +/- 0'.03, respectively. Also, we determined the S-L of BR stars of 0'.85 +/- 0'.05, which closely matches that of the ``young'' RGB stars. Additionally, we found a sequence of peculiar RGB stars and 8 dust-enshrouded stars in the Leo A galaxy.