Pre-Main Sequence Stars in the Orion Nebula Cluster

Abstract:

The complexity of the nature and activity of pre-main-sequence (PMS) stars, as well as the difficulty associated with observing them, requires multiwavelength studies to understand the relationships between PMS evolution, angular momentum (rotation), circumstellar disks, and magnetic fields. In this thesis, the PMS stellar properties of the Orion Nebula Cluster (ONC) were studied by combining the optical and infrared studies of Hillenbrand (1997) and Hillenbrand et al. (1998) with the x-ray and rotational period observations of Gagne et al. (1995) and Stassun et al. (1999). The statistical software package STATISTICA was utilized to combine the data sets, calculate new variables, and produce bi-variate graphs. The multiwavelength study of the ONC showed a PMS stellar population exhibiting high magnetic activity predicted by the dynamo mechanism, as well as continual contractions predicted by evolutionary models.