Stellar Populations of the L1641 South Cluster
Session 49 -- Associations and Clusters
Display presentation, Wednesday, 9:20-6:30, Pauley Room

## [49.13] Stellar Populations of the L1641 South Cluster

Lori E. Allen, Karen M. Strom, and Stephen E. Strom (FCAD, Univ. of Massachusetts)

We present results of a study of a newly discovered young star cluster in the nearby Giant Molecular Cloud L1641. Optical and near-infrared photometry are combined with deep (Imag$<=$16) spectra in the $\lambda$5700 to $\lambda$9000 {\AA} range to derive effective temperatures and bolometric luminosities for the (approximately 100) stars. The cluster population contains both classical and weak-line T-Tauri stars: pre-main sequence, solar-type stars with and without circumstellar accretion disks.

The distribution of the stars in the $L_{bol}$, $T_{eff}$ plane is compared with pre-main sequence evolutionary tracks. The initial mass function for the cluster is discussed, and the dispersion in the ages of the cluster members is examined. The frequency of accretion disks as a function of stellar age is interpreted with regard to the hypothesis that most solar-type stars are initially surrounded by disks, which evolve on timescales on the order of several million years. Finally, we consider the star formation history of the cluster, as indicated by the spatial distributions of masses, ages, and disk frequencies.