Elastic photon scattering from sup 4 He in the. Delta. (1232) region

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5176878

Austin, E J

We have measured the differential cross section at laboratory angles 24{degree}, 30{degree}, 45{degree}, and 60{degree} for the reaction {sup 4}He({gamma},{gamma}){sup 4}He at an average lab energy of 320 MeV. This work was performed at the MIT Bates Linear Accelerator using a bremsstrahlung photon beam produced by a 330 MeV electron beam. The scattered photons were detected with a new, high resolution (1.68% FWHM at 330 MeV) NaI(Tl) total absorption scintillation counter. The data were summed over a nine MeV interval below the endpoint of the elastically scattered photon spectrum. Cosmic ray background was rejected by a plastic scintillator veto shield that surrounded the detector and the energy resolution was sufficient to exclude photons from {pi}{sup 0} decay and inelastic scattering from the region of interest. The results were compared with the predictions of the {Delta}-hole calculations of Koch, Moniz, and Ohtsuka and were found to be in excellent agreement. This measurement is the first unambiguous test of the {Delta}-hole formalism for this reaction near the peak of the {Delta} resonance.

• Research Organization: Boston Univ., MA (USA)
• OSTI ID: 5176878
• Country of Publication: United States
• Language: English

Related Subjects

651220* -- Nuclear Properties & Reactions
A=1-5
Experimental
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACCELERATORS
ANGULAR DISTRIBUTION
CROSS SECTIONS
DATA
DISTRIBUTION
ELASTIC SCATTERING
ENERGY DEPENDENCE
ENERGY RANGE
EXPERIMENTAL DATA
HELIUM 4 TARGET
INFORMATION
LINEAR ACCELERATORS
MATHEMATICAL MODELS
MEV RANGE
MEV RANGE 100-1000
MIT BATES LINAC
NUCLEAR MODELS
NUCLEAR REACTIONS
NUMERICAL DATA
PARTICLE-HOLE MODEL
PHOTONUCLEAR REACTIONS
SCATTERING
TARGETS