Nucleon-nucleon bremsstrahlung at intermediate energies

Journal Article · Fri Feb 01 04:00:00 EST 1991 · Physical Review, C (Nuclear Physics); (USA)

DOI:https://doi.org/10.1103/PhysRevC.43.394· OSTI ID:5844656

Herrmann, V; Speth, J ^[1]; Nakayama, K ^[2]

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1. Institut fuer Kernphysik, Forschungszentrum-Juelich, D-5170 Juelich, Germany (DE)
2. Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602 Institut fuer Kernphysik, Forschungszentrum-Juelich, D-5170 Juelich (Germany)

Energetic photon production in proton-neutron as well as in proton-proton collisions at intermediate bombarding energies are investigated in a meson-exchange potential model calculation in an effort to provide a more reliable basis for calculations of hard photon production in heavy-ion collisions. Special attention is paid to the role of the one-body rescattering contribution, which has been neglected in previous work. It is shown that this contribution enhances the cross section for photon energies only near the maximum value allowed kinematically. As a function of photon energy, both {ital pn} and {ital pp} bremsstrahlung inclusive cross sections are shown to be rather flat except in the low photon energy region. The shape of the angular distribution is, to a large extent, determined by the convection current contribution, which in the soft-photon limit has a well-known dipole shape in the case of {ital pn} bremsstrahlung and a quadrupole shape in the case of {ital pp} bremsstrahlung. For photon energies above {similar to}150 MeV where the magnetic current contribution dominates over the convection contribution, the shape of the angular distribution is roughly of a cos{sup 2}{theta} form. The internal current gives rise to a nearly isotropic angular distribution. The {ital pp}{gamma} cross section is shown to be very small compared to the {ital pn}{gamma} cross section, even for considerably high-energy photons, because of the two-body current contribution, which is mostly absent in {ital pp} bremsstrahlung. The present calculation yields {ital np} bremsstrahlung cross sections which still tend to underpredict the data, although the measurements have large uncertainties.

• OSTI ID: 5844656
• Journal Information: Physical Review, C (Nuclear Physics); (USA), Journal Name: Physical Review, C (Nuclear Physics); (USA) Vol. 43:2; ISSN 0556-2813; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

645202 -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Electromagnetic Interactions & Properties
653003* -- Nuclear Theory-- Nuclear Reactions & Scattering
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANGULAR DISTRIBUTION
BARYON-BARYON INTERACTIONS
BOSON-EXCHANGE MODELS
BOUNDARY CONDITIONS
BREMSSTRAHLUNG
CHARGED-PARTICLE REACTIONS
CROSS SECTIONS
DISTRIBUTION
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
HADRON-HADRON INTERACTIONS
HEAVY ION REACTIONS
INCLUSIVE INTERACTIONS
INTERACTIONS
INVARIANCE PRINCIPLES
LORENTZ INVARIANCE
MASSLESS PARTICLES
MATHEMATICAL MODELS
MATRICES
NUCLEAR REACTIONS
NUCLEON-NUCLEON INTERACTIONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PERIPHERAL MODELS
PHOTONS
PROTON-NEUTRON INTERACTIONS
PROTON-NUCLEON INTERACTIONS
PROTON-PROTON INTERACTIONS
RADIATIONS
RESCATTERING
S MATRIX
SCATTERING