Protostar formation in magnetic molecular clouds beyond ion detachment. I. Formulation of the problem and method of solution

Konstantinos Tassis, Telemachos Ch Mouschovias

Research output: Contribution to journalArticle

Abstract

We formulate the problem of the formation of magnetically supercritical cores in magnetically subcritical parent molecular clouds, and the subsequent collapse of the cores to high densities, past the detachment of ions from magnetic field lines and into the opaque regime. We employ the six-fluid MHD equations, accounting for the effects of grains (negative, positive, and neutral) including their inelastic collisions with other species. We do not assume that the magnetic flux is frozen in any of the charged species. We derive a generalized Ohm's law that explicitly distinguishes between flux advection (and the associated process of ambipolar diffusion) and Ohmic dissipation, in order to assess the contribution of each mechanism to the increase of the mass-to-flux ratio of the central parts of a collapsing core and possibly to the resolution of the magnetic flux problem of star formation. The results, including a detailed parameter study, are presented in two accompanying papers.

Original languageEnglish (US)
Pages (from-to)370-387
Number of pages18
JournalAstrophysical Journal
Volume660
Issue number1 I
DOIs
StatePublished - May 1 2007

Fingerprint

protostars
molecular clouds
detachment
formulations
magnetic flux
ion
ohmic dissipation
dissipation
Ohms law
ambipolar diffusion
ions
advection
collision
inelastic collisions
magnetic field
fluid
star formation
fluids
magnetic fields
method

Keywords

  • Dust, extinction
  • ISM: clouds
  • MHD
  • Magnetic fields
  • Shock waves
  • Stars: formation

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Protostar formation in magnetic molecular clouds beyond ion detachment. I. Formulation of the problem and method of solution. / Tassis, Konstantinos; Mouschovias, Telemachos Ch.

In: Astrophysical Journal, Vol. 660, No. 1 I, 01.05.2007, p. 370-387.

Research output: Contribution to journalArticle

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