The Massive Stellar Population in the Young Association LH 95 in the LMC
  We present a spectroscopic study of the most massive stars in the young (4
Myr old) stellar cluster LH 95 in the Large Magellanic Cloud. This analysis
allows us to complete the census of the stellar population of the system,
previously investigated by us down to 0.4 solar masses with deep HST Advanced
Camera for Surveys photometry. We perform spectral classification of the five
stars in our sample, based on high resolution optical spectroscopy obtained
with 2.2m MPG/ESO FEROS. We use complementary ground-based photometry,
previously performed by us, to place these stars in the Hertzsprung-Russel
diagram. We derive their masses and ages by interpolation from evolutionary
models. The average ages and age spread of the most massive stars are found to
be in general comparable with those previously derived for the cluster from its
low mass PMS stars. We use the masses of the 5 sample stars to extend to the
high-mass end the stellar initial mass function of LH 95 previously established
by us. We find that the initial mass function follows a Salpeter relation down
to the intermediate-mass regime at 2 Msun. The second most massive star in LH
95 shows broad Balmer line emission and infrared excess, which are compatible
with a classical Be star. The existence of such a star in the system adds a
constrain to the age of the cluster, which is well covered by our age and age
spread determinations. The most massive star, a 60-70 Msun O2 giant is found to
be younger (<1 Myr) than the rest of the population. Its mass in relation to
the total mass of the system does not follow the empirical relation of the
maximum stellar mass versus the hosting cluster mass, making LH 95 an exception
to the average trend.
