An absolute measurement of the photodisintegration of Helium-4

A measurement of the differential cross section has been performed for the photodisintegration of ⁴He into a proton plus a triton. This reaction is highly sensitive to the electromagnetic currents in the nucleus which arise from the exchange of mesons between nucleons. The study of light nuclei such as ⁴He, whose nucleonic structure is the simplest, holds the promise of perfecting a microscopic theory of nuclear dynamics, in which nuclear structure and reactions are understood in terms of fundamental particle interactions. The measurement was performed with a tagged-photon beam, using a large solid-angle charged particle detector developed for this and other similar experiments. The measurement was performed within the photon energy range between 63 and 71 MeV, and divided into four energy bins of 2 MeV each. The measurement of the differential cross section was confined to the angular range 36°-141° in the center-of-mass reference frame. The total cross section was determined to within a total uncertainty of 5%. The angular distribution was fitted to an expansion of Legendre polynomials in cos <i>θ</i> including terms of order 0-3. This measurement is in agreement with a previous measurement, and improves on the precision of the total cross section from the previous measurement by a factor of 6. A comparison is made with several theoretical calculations, and a qualitative agreement is found. These data suggest refinements to these calculations, in order to account for the quantitative differences.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Physics

Department dc:contributor.department

Physics

Grantor dc:publisher

Virginia Polytechnic Institute and State University

Year dc:date.issued

1988

Author dc:creator

• Jones, Richard Thurston

Chair dc:contributor.committeechair

• Jenkins, David A.

Committee members dc:contributor.committeemember

• Ritter, Alfred "Jimmy"
• Mizutani, Tetsuro
• Ficenec, John R.
• Debevec, P.T.
• Schutt, D.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/53539

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/53539