The photoneutron yield predictions by PICA and comparison with the measurements

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:393301

Job, P K ^[1]; Gabriel, T A ^[2]

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1. Argonne National Lab., IL (United States)
2. Oak Ridge National Lab., TN (United States)

The photoneutron yields at higher photon energies have become very important since the advent of high energy electron accelerators. Bremsstrahlung is produced when the particle beam interacts with the storage-ring components or residual-gas molecules in the storage-ring vacuum. Bremsstrahlung thus produced interacts with the high-Z materials in the beamline like the beam dumps and collimators to produce photoneutrons. There are three modes of neutron production by bremsstrahlung. At low energies ({>=}525 MeV), photons are absorbed by the dipole interaction and the compound nucleus thus formed decays emitting protons and neutrons and other heavier particles. At higher energies ({>=}25 MeV), photon interacts with the nucleus through absorption on a quasi-deuteron, which subsequently decays producing a neutron and proton pair which can interact with the rest of the nucleus. At still higher energies the photopion production becomes possible and competes with the quasi-deuteron process. In this paper we have calculated the photoneutron yield from a thick copper target using the photonuclear interaction code PICA. Using this as the neutron source, we have calculated the dose rates through heavy concrete and compared it with the measurements made at the Advanced Photon Source at Argonne National Lab.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 393301
• Report Number(s): CONF-9510398--1; ON: DE97000013
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
43 PARTICLE ACCELERATORS
66 PHYSICS
BREMSSTRAHLUNG
DOSE RATES
NEUTRON DETECTION
P CODES
PHOTONEUTRONS
PHOTONUCLEAR REACTIONS
RADIATION DOSES
SHIELDING