A&A 441, 153-158 (2005)
Ambipolar diffusion in self-gravitating filamentsH.-E. Fröhlich
Astrophysikalisches Institut Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany
(Received 23 July 2004 / Accepted 10 May 2005)
One-dimensional similarity solutions for a collapsing, homogeneous, infinitely long cylinder that is subject to ambipolar diffusion are given. There is an analytical solution with infinite density being reached after 4.3 free-fall times. In that case the magnetic field strength Bz on the axis scales like with density . The analytical solution proves "attractive". Even if the initial conditions depart slightly from those of the analytical solution, that solution is nevertheless approached through damped oscillations.
Key words: magnetohydrodynamics (MHD) -- stars: formation -- ISM: clouds -- ISM: magnetic fields
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