IN-SYNC II: Virial Stars from Sub-Virial Cores -- The Velocity Dispersion of Embedded Pre-Main-Sequence Stars in NGC 1333

Abstract

The initial velocity dispersion of newborn stars is a major unconstrained aspect of star formation theory. Using near-infrared spectra obtained with the APOGEE spectrograph, we show that the velocity dispersion of young (1-2 Myr) stars in NGC 1333 is 0.92+/-0.12 km/s after correcting for measurement uncertainties and the effect of binaries. This velocity dispersion is consistent with the virial velocity of the region and the diffuse gas velocity dispersion, but significantly larger than the velocity dispersion of the dense, star-forming cores, which have a sub-virial velocity dispersion of 0.5 km/s. Since the NGC 1333 cluster is dynamically young and deeply embedded, this measurement provides a strong constraint on the initial velocity dispersion of newly-formed stars. We propose that the difference in velocity dispersion between stars and dense cores may be due to the influence of a 70 micro-Gauss magnetic field acting on the dense cores, or be the signature of a cluster with initial sub-structure undergoing global collapse.

Accepted to ApJ. 23 pages, 9 figures and 3 tables

References in corpus (17)

• Theory of Star Formation
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• The Dartmouth Stellar Evolution Database
• A Spitzer Survey of Young Stellar Clusters within One Kiloparsec of the Sun: Cluster Core Extraction and Basic Structural Analysis
• Spitzer Observations of NGC 1333: A Study of Structure and Evolution in a Nearby Embedded Cluster
• The Effects of Radiative Transfer on Low-Mass Star Formation
• CO Isotopologues in the Perseus Molecular Cloud Complex: the X-Factor and Regional Variations
• The COMPLETE Survey of Star-Forming Regions: Phase I Data
• The Nature of the Dense Core Population in the Pipe Nebula: Thermal Cores Under Pressure
• Equilibrium Star Cluster Formation
• On the Rapid Collapse and Evolution of Molecular Clouds
• An Ammonia Spectral Atlas of Dense Cores in Perseus
• Dynamics of Dense Cores in the Perseus Molecular Cloud
• Kinematic Structure of the Orion Nebula Cluster and its Surroundings
• Young Stellar Object Variability (YSOVAR): Long Timescale Variations in the Mid-Infrared
• IN-SYNC I: Homogeneous Stellar Parameters from High Resolution APOGEE Spectra for Thousands of Pre-main Sequence Star
• A Spectroscopic Study of Young Stellar Objects in the Serpens Cloud Core and NGC 1333

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