The Local Group Dwarf Galaxies: The Star Formation Histories derived
  using the Long Period Variable stars
  Dwarf galaxies in the Local Group (LG) represent a distinct as well as
diverse family of tracers of the earliest phases of galaxy assembly and the
processing resulting from galactic harassment. Their stellar populations can be
resolved and used as probes of the evolution of their host galaxy. In this
regard, we present the first reconstruction of the star formation history (SFH)
of them using the most evolved AGB stars that are long period variable (LPV).
For the nearby, relatively massive and interacting gas-rich dwarf galaxies, the
Magellanic Clouds, we found that the bulk of the stars formed ~ 10 Gyr ago for
the LMC, while the strongest episode of star formation in the SMC occurred a
few Gyr later. A peak in star formation around 0.7 Gyr ago in both Clouds is
likely linked to their recent interaction. The Andromeda satellite pair
NGC147/185 show different histories; the main epoch of star formation for NGC
185 occurred 8.3 Gyr ago, followed by a much lower, but relatively constant
star formation rate (SFR). In the case of NGC 147, the SFR peaked only 6.9 Gyr
ago, staying intense until ~ 3 Gyr ago. Star formation in the isolated gas-rich
dwarf galaxy IC 1613 has proceeded at a steady rate over the past 5 Gyr,
without any particular dominant epoch. Due to lack of sufficient data, we have
conducted an optical monitoring survey at the Isaac Newton Telescope (INT) of
55 dwarf galaxies in the LG to reconstruct the SFH of them uniformly. The
observations are made over ten epochs, spaced approximately three months apart,
as the luminosity of LPV stars varies on timescales of months to years. The
system of galactic satellites of the large Andromeda spiral galaxy (M31) forms
one of the key targets of our monitoring survey. We present the first results
in the And I dwarf galaxy, where we discovered 116 LPVs among over 10,000
stars.
