EPoS Contribution
EPoS Contribution
Studying Intermediate Mass Star Formation in the Carina Nebula with HH Jets

Megan Reiter
University of Arizona, Tucson, Arizona, USA
We present preliminary results from an ongoing study of accretion and outflow in intermediate mass (IM) stars, focusing on a sample of outflow sources identified in the Carina nebula. Recent H-alpha imaging of the Carina nebula with HST/ACS led to the discovery of 40 new Herbig-Haro (HH) jets. H-alpha determined jet mass loss rates and mass accretion rates estimated from model fits to the IR SED of jet driving sources indicate that these outflows are driven by IM protostars (~1-8 Msun). Far less is known about the early accretion phases of intermediate mass stars compared with their low-mass counterparts. Given that the longest HH flows record the mass loss history of their driving source over a significant fraction of their accretion age, these flows provide important clues about the accretion history of this unique sample of intermediate mass stars. With independent estimates of the accretion rate from the IR SEDs, we can compare the jet efficiency (Mjet / Macc) of these IM protostars with efficiencies measured for low-mass protostars. Together, the HH jets in the Carina nebula provide a sample of these rare IM protostars in a relatively nearby and well-constrained laboratory, allowing for the systematic investigation of the mass accretion behavior forming protostars in the critical transition between low- and high-mass star formation.
Collaborators:
N. Smith, University of Arizona, USA
P. Hartigan, Rice University, USA
J. Bally, University of Colorado - Boulder, USA