Quasideuteron mechanism and the photodisintegration of /sup 4/He at intermediate energies

Journal Article · Wed Sep 01 04:00:00 EDT 1976 · Phys. Rev., C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.14.1133· OSTI ID:7266754

Noguchi, C T; Prats, F

The /sup 4/He(..gamma.., p)/sup 3/H and /sup 4/He(..gamma.., n)/sup 3/He reactions from E/sub ..gamma../ > or approx. = 60 MeV to E/sub ..gamma../ < or approx. = 170 MeV are considered, along with the /sup 4/He(..gamma.., pnd) reaction from threshold up to intermediate energies. The absorption of photons in the intermediate energy range up to pion threshold is expected to occur predominately via the quasideuteron mechanism as is indicated from the reaction /sup 4/He(..gamma.., pnd). For the (..gamma.., pnd) amplitude, the breakup of /sup 4/He into a deuteron and quasideuteron is calculated using a /sup 4/He Gaussian ground-state wave function fitted to the form factor, a quasideuteron S-wave scattered state, and a deuteron effective range wave function. The photobreakup of the quasideuteron can be expressed in terms of the amplitude for the photobreakup of the deuteron as shown by Levinger. The photoamplitude for the (..gamma.., pnd) reaction is used to obtain the photoamplitude for the (..gamma.., n) and (..gamma.., p) reactions. The contribution to the (..gamma.., p) and (..gamma.., n) reactions from the quasideuteron mechanism is calculated as a rescattering of a nucleon--deuteron pair to form a triton. For both nucleon--triton reactions, this yields angular distributions with forward peaking in agreement with the forward asymmetry obtained experimentally. The cross section at intermediate energy appears to be dominated by the quasideuteron effect. Finally, the alternative quasideuteron calculation using nucleon--nucleon short-range correlations is shown to be equivalent to the present quasideuteron calculation. (AIP)

• Research Organization: Department of Physics, The George Washington University, Washington, D.C. 20052
• OSTI ID: 7266754
• Journal Information: Phys. Rev., C; (United States), Journal Name: Phys. Rev., C; (United States) Vol. 14:3; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

651215* -- Nuclear Properties &amp; Reactions
A=1-5
Theoretical-- Nuclear Reactions &amp; Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
AMPLITUDES
ANGULAR DISTRIBUTION
BARYONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BREAKUP REACTIONS
CHARGED PARTICLES
DEUTERONS
DISTANCE
DISTRIBUTION
ELEMENTARY PARTICLES
ENERGY LEVELS
ENERGY RANGE
EVEN-ODD NUCLEI
FERMIONS
FORM FACTORS
GROUND STATES
HADRONS
HELIUM 3
HELIUM 4 TARGET
HELIUM ISOTOPES
HYDROGEN ISOTOPES
INTERACTION RANGE
ISOTOPES
KINETICS
LIGHT NUCLEI
MEV RANGE
MEV RANGE 10-100
MEV RANGE 100-1000
NEUTRONS
NUCLEAR REACTION KINETICS
NUCLEAR REACTIONS
NUCLEI
NUCLEONS
ODD-EVEN NUCLEI
PARTICLE PROPERTIES
PHOTONUCLEAR REACTIONS
PROTONS
QUASI PARTICLES
RADIOISOTOPES
REACTION KINETICS
RESCATTERING
SCATTERING
SCATTERING AMPLITUDES
STABLE ISOTOPES
TARGETS
TRITIUM
YEARS LIVING RADIOISOTOPES