Balmer alpha emission and hydrogen atom energy in ion-source discharges

Technical Report · Wed Jul 01 00:00:00 EDT 1981

DOI:https://doi.org/10.2172/6187050· OSTI ID:6187050

McNeill, D H; Kim, J

The structure of the hydrogen Balmer alpha line emission profiles from three types of neutral beam injector ion source plasmas (filling pressure approx. 10 mTorr, electron density approx. 1 to 2 x 10/sup 12/ cm/sup -3/, electron temperature approx. 2 to 4 eV) is studied with the aid of a simple model for the neutral particle balance and H/sub ..cap alpha../ emission. A large fraction of the H/sub ..cap alpha../ is produced by dissociative excitation of H/sub 2/ and dissociative recombination of H/sub 2//sup +/, while the remainder is produced by excitation of H atoms, most of which have energies that are close to the characteristic H/sub 2/ dissociation energies. The H/sub ..cap alpha../ linewidth is thus insensitive to the discharge operating conditions and equals approx. 0.27 A when only slow (approx. 0.3 eV) dissociatively excited atoms are present or approx. 0.35 A when fast (> 1 eV) atoms, apparently also produced in dissociation reactions, are present as well.

• Research Organization: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); General Atomics, San Diego, CA (United States)
• DOE Contract Number: AM02-76CH03073
• OSTI ID: 6187050
• Report Number(s): PPPL-1797; ON: DE81023973; TRN: 81-013039
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ION SOURCES
EMISSION SPECTRA
ENERGY SPECTRA
ALPHA PARTICLES
BALMER LINES
HYDROGEN
HYDROGEN IONS 2 PLUS
CATIONS
CHARGED PARTICLES
ELEMENTS
HYDROGEN IONS
IONS
MOLECULAR IONS
NONMETALS
SPECTRA
700205* - Fusion Power Plant Technology- Fuel
Heating
& Injection Systems