Measurement of the ion dynamic effect on the H/sub. cap alpha. / and D/sub. cap alpha. / lines at low electron densities

Journal Article · Sun Mar 15 04:00:00 EST 1987 · Phys. Rev. A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.35.2596· OSTI ID:6835758

Sanchez, A; Fulton, R D; Griem, H R

The line profiles of the Balmer ..cap alpha.. transitions of hydrogen and deuterium were measured simultaneously in a theta-discharge plasma. The characteristics of the light source were the following: peak electron density of the order of 7 x 10/sup 14/ cm/sup -3/, electron temperatures between 15 and 20 eV, and neutral and ion temperatures between 2.5 and 3.5 eV. The filling gas was helium with a 1% admixture of equal parts of hydrogen and deuterium. The experimental profiles were compared with a theoretical spectrum that was calculated taking into account the Stark broadening, independent Gaussian widths for each line, a fine-structure correction, and the instrumental broadening. In the data reduction a correction of the experimental data was made to allow for a radial inhomogeneity of the plasma. The measurements confirm the existence of large deviations from calculated profiles that do not account for ion dynamical effects. It has also been found that a model to include ion dynamical effects as a Gaussian broadening partly corrects the discrepancies. Finally, about 10% agreement is obtained when Lorentzian profiles based on relaxation theory calculations are used for the Stark broadening. Similar agreement is obtained with numerically simulated profiles.

• Research Organization: Laboratory for Plasma and Fusion Energy Studies, University of Maryland, College Park, Maryland 20742
• OSTI ID: 6835758
• Journal Information: Phys. Rev. A; (United States), Journal Name: Phys. Rev. A; (United States) Vol. 35:6; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
BALMER LINES
BUFFERS
DEUTERIUM
DOPPLER BROADENING
ELECTRON DENSITY
ELEMENTS
FLUIDS
GASES
HELIUM
HYDROGEN
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
LINE BROADENING
LINE WIDTHS
NONMETALS
NUCLEI
ODD-ODD NUCLEI
PLASMA
RARE GASES
STABLE ISOTOPES
STARK EFFECT