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Title: ENVIRONMENT AND PROTOSTELLAR EVOLUTION

Even today in our Galaxy, stars form from gas cores in a variety of environments, which may affect the properties of the resulting star and planetary systems. Here, we study the role of pressure, parameterized via ambient clump mass surface density, on protostellar evolution and appearance, focusing on low-mass Sun-like stars and considering a range of conditions from relatively low pressure filaments in Taurus, to intermediate pressures of cluster-forming clumps like the Orion Nebula Cluster, to very high pressures that may be found in the densest infrared dark clouds or in the Galactic center. We present unified analytic and numerical models for the collapse of prestellar cores, accretion disks, protostellar evolution, and bipolar outflows, coupled with radiative transfer calculations and a simple astrochemical model to predict CO gas-phase abundances. Prestellar cores in high-pressure environments are smaller and denser and thus collapse with higher accretion rates and efficiencies, resulting in higher luminosity protostars with more powerful outflows. The protostellar envelope is heated to warmer temperatures, affecting infrared morphologies (and thus classification) and astrochemical processes like CO depletion onto dust grain ice mantles (and thus CO morphologies). These results have general implications for star and planet formation, especially via their effect onmore » astrochemical and dust grain evolution during infall to and through protostellar accretion disks.« less
Authors:
 [1] ;  [2]
  1. Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile)
  2. Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States)
Publication Date:
OSTI Identifier:
22518831
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 802; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; CARBON MONOXIDE; DENSITY; FILAMENTS; GALAXIES; ICE; LUMINOSITY; MASS; MORPHOLOGY; NEBULAE; PLANETS; PROTOSTARS; RADIANT HEAT TRANSFER; STAR CLUSTERS; STAR EVOLUTION; SUN