Astrophysical plasmas

A. Dalgarno and D. Leyzer (eds). Spectroscopy of Astrophysical Plasmas, Cambridge University Press, London, 1987. 

The quantity in the right-hand side of (21) is called the helicity of the vector b and is used in several contexts, mainly in fluid and in plasma physics. The term was coined by Moffatt in 1969 in a paper on tangled vorticity lines [44] with the velocity of a fluid v and its vorticity oa= V x v as the vectors a and b. The magnetic helicity h [ A BrfV is useful to study the magnetic configurations in astrophysical plasmas and in tokamaks. 

Dalgarno A and Fox J 1994 Ion chemistry in atmospheric and astrophysical plasmas Unimolecular and Bimolecular Ion-Molecule Reaction Dynamics ed C-Y Ng, T Baer and I Powis (New York Wiley)... 

Applications of Atomic Physics to Astrophysical Plasmas Carole Jordan... 

ABSTRACT. A review is presented of charge transfer reactions of multiply charged ions with atomic hydrogen and helium in astrophysical plasmas. 

For the typical densities of astrophysical plasmas, where multiply charged ions are observed, 3-body reactions are of negligible importance and recombination can take place only by three distinct modes ... 

Adopting typical values of the corresponding rate coefficients for reactions (1.1), (1.2) and (1.3) under favourable circumstances, it is easily seen that provided the neutral densities are of the order of 10 ng or greater (n is the electron density) charge transfer can become the dominant mechanism for recombination. Such is the case in most astrophysical plasmas for temperatures not exceeding 10 K. 

A. Dalgarno, D. Layzer (eds) Spectroscopy of Astrophysical Plasmas (Cambridge Univ. Press, Cambridge 1987)... 

Fundamental quantities, such as wavelengths and tramsition probabihties, determined using spectroscopy, for atoms and molecules are of direct importance in several disciplines such as astrophysics, plasma and laser ph5 ics. Here, as in many fields of applied spectroscopy, the spectroscopic information can be used in various kinds of analysis. For instance, optical atomic absorption or emission spectroscopy is used for both qualitative and quantitative chemical analysis. Other types of spectroscopy, e.g. electron spectroscopy methods or nuclear magnetic resonance, also provide information on the chemical environment in which a studied atom is situated. Tunable lasers have had a major impact on both fundamental and applied spectroscopy. New fields of applied laser spectroscopy include remote sensing of the environment, medical applications, combustion diagnostics, laser-induced chemistry and isotope separation. 

S. Johansson, V.S, Letokhov Radiative cycle with stimulated emission from atoms amd ions in an astrophysical plasma. Phys. Rev. Lett. 90, 011101 (2003)... 

Dalgamo A, Fox JL (1994) Ion chemistry in atmospheric and astrophysical plasmas. In Ng CY, Baer T, Powis I (eds) Unimolecular and bimolecular ion-molecule reaction dynamics, Wiley series in ion chemistry and physics. Wiley, Chichester, Chapter 1... 

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