NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Primordial stellar evolution - The protostar phaseThe structure and evolution of a protostar forming from a cloud composed of pure hydrogen and helium gas are calculated. Using an accretion rate of 0.0044 solar mass/yr, the collapse of the cloud is followed numerically as a sequence of steady state accretion flows onto the hydrostatic core, which grows from an initial mass of 0.01 solar mass to 10.5 solar masses. The core is surrounded by an optically thick radiative precursor for most of its evolution. The core radius reaches 47 solar radii when the mass is 1 solar mass. For sufficiently massive cores, the deep interior contracts strongly, driving out a 'luminosity wave' which reaches the surface when the mass is 8 solar masses. This results in a large increase in core radius, the establishment of surface convection, and the disappearance of the radiative precursor. The dependence of core radius on the mass and accretion rate is analytically derived, and a new table or Rosseland mean opacities for metal-free gas is presented.
Document ID
19860046694
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Stahler, S. W.
(Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Palla, F.
(Arcetri Osservatorio Astrofisico, Florence, Italy)
Salpeter, E. E.
(Cornell University Ithaca, NY, United States)
Date Acquired
August 12, 2013
Publication Date
March 15, 1986
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 302
ISSN: 0004-637X
Subject Category
Astrophysics
Accession Number
86A31432
Funding Number(s)
CONTRACT_GRANT: NSF AST-84-15162
CONTRACT_GRANT: NAGW-246
CONTRACT_GRANT: NSF AST-81-16370
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available