Photon scattering from {sup 12}C and {sup 4}He nuclei near the {Delta}(1232) resonance

Journal Article · Tue Aug 01 04:00:00 EDT 1995 · Physical Review, C

DOI:https://doi.org/10.1103/PhysRevC.52.755· OSTI ID:112953

Igarashi, R; Bergstrom, J C; Caplan, H S; Doss, K G.E.; Hallin, E L; Skopik, D M ^[1]; Delli Carpini, D; Booth, E C; McIntyre, E K; Miller, J P ^[2]; Lucas, M A; MacGibbon, B E; Nathan, A M; Wells, D ^[3]

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1. Saskatchewan Accelerator Laboratory, University of Saskatchewan, 107 North Road, Saskatoon, Saskatchewan S7N 5C6 (Canada)
2. Department of Physics, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215 (United States)
3. Department of Physics, University of Illinois at Urbana-Champaign, Nuclear Physics Laboratory, Champaign, Illinois 61820 (United States)

Angular distributions for photon scattering from {sup 12}C and {sup 4}He have been measured using continuous wave bremsstrahlung from the Saskatchewan Accelerator Laboratory pulse stretcher ring. Data for carbon were taken at 158.8, 195.2, 197.2, 247.2, and 290.2 MeV end-point energies, and for helium were taken at an end-point energy of 158.8 MeV. A large NaI(Tl) gamma ray spectrometer with 1.7% resolution was used to detect the scattered photons at laboratory scattering angles ranging from 20{degree} to 150{degree}. The excellent energy resolution of the NaI detector allowed a separation of elastic from inelastic photon scattering for the first time at these energies. The angular distributions for elastic scattering are in only fair agreement with delta-hole theory and theory based on the optical theorem at forward angles, and completely disagree with theory at backward angles. Measured cross sections for inelastic scattering leading to the 4.43 MeV state in carbon are small compared to the elastic scattering at forward angles, but are dominant at backward angles. This experiment is the first to separate elastic from inelastic photon scattering at these energies.

• OSTI ID: 112953
• Journal Information: Physical Review, C, Journal Name: Physical Review, C Journal Issue: 2 Vol. 52; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ANGULAR DISTRIBUTION
BREMSSTRAHLUNG
CARBON 12 TARGET
CROSS SECTIONS
DELTA BARYONS
GAMMA SPECTROMETERS
HELIUM 4 TARGET
INELASTIC SCATTERING
MEV RANGE 100-1000
PHOTONUCLEAR REACTIONS