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Description
We report on the accretion properties of low-mass stars in the LH 95 association within the Large Magellanic Cloud. Using noncontemporaneous wideband optical and narrowband H{alpha} photometry obtained with the Hubble Space Telescope, we identify 245 low-mass pre-main-sequence (PMS) candidates showing H{alpha} excess emission above the 4{sigma} level. We derive their physical parameters, including effective temperatures, luminosities, masses (M_*_), ages, accretion luminosities, and mass accretion rates (dM/dt_acc_). We identify two different stellar populations: younger than ~8Myr with median dM/dt_acc_~5.4x10^-8^M_{sun}_/yr (and M_*_~0.15-1.8M_{sun}_) and older than ~8Myr with median dM/dt_acc_~4.8x10^-9^M_{sun}_/yr (and M_*_~0.6-1.2M_{sun}_). We find that the younger PMS candidates are assembled in groups around Be stars, while older PMS candidates are uniformly distributed within the region without evidence of clustering. We find that dM/dt_acc_ in LH 95 decreases with time more slowly than what is observed in Galactic star-forming regions (SFRs). This agrees with the recent interpretation, according to which higher metallicity limits the accretion process in both rate and duration due to higher radiation pressure. The dM/dt_acc_-M_*_ relationship shows different behavior at different ages, becoming progressively steeper at older ages, indicating that the effects of mass and age on dM/dt_acc_ cannot be treated independently. With the aim to identify reliable correlations between mass, age, and dM/dt_acc_, we used a multivariate linear regression fit between these parameters for our PMS candidates. The comparison between our results and those obtained in other SFRs of our Galaxy and the Magellanic Clouds confirms the importance of the metallicity for the study of the dM/dt_acc_ evolution in clusters with different environmental conditions.
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