 |
|
| EPoS Contribution |
|
Properties of YSOs in the NGC 1333 and Serpens Embedded Clusters
Elaine M. Winston University of Exeter, Exeter, UK | |
| I will present new Chandra X-ray data of the NGC 1333 embedded cluster combining these with Spitzer & Chandra photometry and ground based spectroscopy of both the NGC 1333 and Serpens Cloud Core clusters to perform a detailed study of the properties of two of the nearest embedded clusters to the Sun. Firstly, I present new, deeper observations of NGC 1333 with Chandra ACIS-I and combine these with existing Spitzer observations of the region. In NGC 1333, a total of 86 cluster member are detected in X-rays, of which 54 were previously identified in the Spitzer data. Of the Spitzer identified sources, 22.7% of the Class I protostars are detected, 53.3% of the Flat Spectrum sources, 52% of the Class II, and 50% of the Transition Disk YSOs. Thirty two new Class III members of the cluster are identified, bringing the total identified YSO population to 169. I will then present far-red (600-900nm) and near-IR (H & K band) spectra of 130 YSOs in the two clusters. These spectral are used to determine effective temperature and bolometric luminosity, and to contruct HR diagrams of the two clusters. The isochronal ages of the Class II and Class III sources will be shown to be indistinguishable. I will also show that the young sources (<3 Myrs) are more centraly concentrated, while the older sources are more dispersed. The X-ray Luminosity Functions (XLFs) of the NGC 1333 and Serpens clusters are compared to each other and the Orion Nebula Cluster. Based on a comparison of the XLFs to the ONC, I will present a new distance for the Serpens cluster of 360 pc. Comparing with spectral types, the X-ray luminosity is shown to depend on the calculated bolometric luminosity as in other regions. Examining the dependance of L_X on effective temperature and stellar surface area, L_X is shown to depend primarily on the surface area. In NGC 1333, I will speculate that a small jump in the X-ray luminosity between spectral types of M0 and K7 results from the presence of radiative zones in the K-stars. The gas to dust ratio of the NGC 1333 cluster was examined using the Hydrogen column density and K-band extinction. The NGC 1333 N_H v A_K ratio is found to be lower than expected of the ISM, similar to Serpens and indicative of grain growth, but dissimilar to the more massive RCW 38 region, which resembles the ISM ratio. | |
 | |
| Caption: credit: R. Gutermuth, University of Massachusetts, USA (Co-I). Spitzer IRAC 3-band image of the NGC 1333 star forming region. Blue is 3.6 microns, green is 4.5 microns, red is 8.0 microns. Diffuse PAH emission is shown in red. Emission from shocked hydrogen, indicative of jets, is visible in green. | |
| Collaborators: S.T. Megeath, University of Toledo, USA S.J. Wolk, CfA, USA R. Gutermuth, University of Massachusetts, USA L.E. Allen, NOAO, USA J. Hernandez, CIDA, Venezuela K. Covey, CfA, USA J. Muzerolle, STScI, USA J.L. Hora, CfA, USA B. Spitzbart, CfA, USA P. Myers, CfA, USA G.G. Fazio, CfA, USA |
Key publication
Suggested Session: Early Phases of Disks |