Operation of a plasma-focus device with D/sub 2/ and He/sup 3/

Journal Article · Thu Sep 01 04:00:00 EDT 1977 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.324287· OSTI ID:7318746

Gullickson, R L; Luce, J S; Sahlin, H L

Two plasma-focus devices at the Lawrence Livermore Laboratory, the B Division device (BDPF), with a stored energy of 73 kJ at 18 kV, and the Physics Department device (PDPF), with a stored energy of 67 kJ at 20 kV, were operated with various mixtures of D/sub 2/ and He/sup 3/. The purpose of the experiments was to evaluate the D-D/D-He/sup 3/ yield ratio as a diagnostic tool for determining the plasma ion temperature. Measurements were made in the high-pressure mode (total pressure of 4.0 Torr for the BDPF, 7.5 Torr for the PDPF), where previous measurements using carbon activation showed no significant ion acceleration to energies above the 330-keV carbon (d,n) reaction threshold. The yield from the D(d,n)He/sup 3/ reaction was determined from measurements of the total neutron yield using the standard silver-activation technique. The yield from the He/sup 3/(d,p) He/sup 4/ reaction was determined by measuring the reaction-product protons by copper activation. The Cu anode insert from the center electrode was analyzed for ..gamma.. activity following each series of shots to measure the presence of Zn/sup 63/ from the 4.21-MeV-threshold Cu/sup 63/(p,n)Zn/sup 63/ reaction. The thick-target yield for this reaction at the proton energy of 14.6 MeV was calculated from cross-section data, giving a value of 7.5 x 10/sup -4/ Zn/sup 63/ atoms per incident proton. In operation with 50/50 atomic or molecular mixtures of D/sub 2/ and He/sup 3/, the D-D/D-He/sup 3/ yield ratio varied from a minimum of 13.6 to a maximum of 60.5. This corresponds to a plasma temperature range from 4.0 to 6.5 keV, or if a beam-target model is assumed, to a deuteron beam ranging in energy from 28 to 47 keV incident upon stationary He/sup 3/ ions. Operating with fractions of He/sup 3/ ranging from 0.053 to 1.0 at a total pressure of 4 Torr, the D-D neutron yield showed the expected dependence on the square of the deuterium fraction (f (D)).

• Research Organization: Lawrence Livermore Laboratory, University of California, Livermore, California 94550
• OSTI ID: 7318746
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 48:9; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700106* -- Fusion Energy-- Plasma Research-- Plasma Production-- (-1987)
ACTIVATION ANALYSIS
BARYONS
CHEMICAL ANALYSIS
DEUTERIUM
ELEMENTARY PARTICLES
EVEN-ODD NUCLEI
FERMIONS
GAMMA SPECTRA
HADRONS
HEATING
HELIUM 3
HELIUM ISOTOPES
HYDROGEN ISOTOPES
ION TEMPERATURE
ISOTOPES
KINETICS
LIGHT NUCLEI
NEUTRON DENSITY
NUCLEAR REACTION KINETICS
NUCLEAR REACTIONS
NUCLEI
NUCLEONS
NUCLEOSYNTHESIS
ODD-ODD NUCLEI
OPEN PLASMA DEVICES
OPERATION
PINCH EFFECT
PLASMA DIAGNOSTICS
PLASMA FOCUS
PLASMA FOCUS DEVICES
PLASMA HEATING
PROTONS
REACTION KINETICS
SPECTRA
STABLE ISOTOPES
THERMONUCLEAR DEVICES
THERMONUCLEAR REACTIONS