title: High-flux beam source of fast neutral helium.
abstract: A high-flux beam source of fast neutral helium has been constructed by extending the designs of previous authors. The source is a dc or pulsed electric discharge in an expanding gas nozzle. The beam produced has a flux on the order of 10(15) atoms/s sr and a mean velocity on the order of 10(7) cm/s. The composition of the beam has been determined by the use of particle detectors and by the observation of the excitation of certain target gases. An upper bound of 3.7 x 10(-5) has been estimated for the He(2(3)S(1))/He((1)S(0))beam density ratio and a value of 0.2 found for the He(+)/He(1(1)S(0)) beam density ratio.
authors.affiliation: Physics Department, University of Missouri, Rolla, MO 65401, USA.
authors.forename: D W
authors.initials: DW
authors.lastname: Fahey
authors.forename: L D
authors.initials: LD
authors.lastname: Schearer
authors.forename: W F
authors.initials: WF
authors.lastname: Parks
mesh_terms: D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D020450:Heavy Ions; D010315:Particle Accelerators / Q000295:instrumentation*; D011829:Radiation Dosage