Measurements of multiple scattering, range, and range straggling of low energy pions and muons

Using a stack of multiwire proportional chambers with interspersed absorbers, the ranges and directions of low energy pions and muons have been measured. By simultaneously determining both the directions of negative muons incident upon and scattered from thin sheets of galvanized steel, aluminum, and polyethylene, and the ranges of these muons in the proportional chamber stack, their multiple scattering as a function of energy has been obtained. The measured rms projected multiple scattering angle was fitted to a linear function of the values predicted by the Moliere theory: θ^proj_rms (expt.) = C[θ^proj_rms(theor.)] ± D. The results were C = 0.861 ± 0.012, D = 0.219° ± 0.176° for galvanized steel (thickness 0.608 gm/cm²); C = 1.05 ± 0.05, D = -0.148° ± 0.126° for aluminum (0.429 gm/cm²); and C = 1.02 ± 0.06, D = 0.259° ± 0.086° for polyethylene (0.297 gm/cm²). Also the range distributions of positive muons and positive and negative pions at various energies were measured, and the mean range and range straggling (deviation about the mean) were obtained and compared with the calculations of Janni •. The percent differences between the actual incident energies (measured in a magnetic spectrometer) and those calculated from the mean range were 2.37% for 39.32 MeV µ⁺, 1.31% for 37.62 MeV π⁺, 0.608% for 33.00 MeV π⁺, 0.303% for 33.00 MeV π⁻, and 0.854% for 37.62 MeV π⁻. These results are all within the expected accuracy of the range calculations~ The ratios of the observed to the predicted range straggling for the corresponding particles and energies were 1.00, 1.20, 1.40, 1.40, and 1.20. The straggling of pions may appear to be 20-40% larger than range theory predicts perhaps because of the. effects of the strong interactions of pions with the nuclei of atoms in the stopping material.

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

1975

Author dc:creator

• Lagerland, Terrence Daniel

Statement dc:rights

• In Copyright

Licence dc:rights.uri

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

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10919/104340

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/104340