Chapter

Elementary excitation processes in rarefied plasmas

Vladilen Letokhov and Sveneric Johansson

in Astrophysical Lasers

Published in print December 2008 | ISBN: 9780199548279
Published online May 2009 | e-ISBN: 9780191720512 | DOI: http://dx.doi.org/10.1093/acprof:oso/9780199548279.003.0004
 Elementary excitation processes in rarefied plasmas

Show Summary Details

Preview

An atom (ion) in a rarefied astrophysical plasma near a hot (blue) star takes part in a chain of radiative and collisional processes initiated by the UV radiation from the star. The main constituents of an astrophysical plasma are hydrogen (90% of the atoms) and helium (10%) with the ionization potentials I(H) = 13.6 eV and I(He) = 24.6 eV, respectively. This chapter focuses on processes that involve the hydrogen atom. Topics discussed include photoionization of atoms, recombination, electron excitation and ionization, total and local thermodynamic equilibrium (LTE), non-LTE astrophysical media, and photoselective excitation.

Keywords: photoionization; electron excitation; thermodynamic equilibrium; photoselective excitation

Chapter.  3769 words.  Illustrated.

Subjects: Atomic, Molecular, and Optical Physics

Full text: subscription required

How to subscribe Recommend to my Librarian

Buy this work at Oxford University Press »

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.