Capture Cross Section of C¹³ for Low Energy Protons

Citation

Woodbury, Eric John (1951) Capture Cross Section of C¹³ for Low Energy Protons. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/9KQX-4335. https://resolver.caltech.edu/CaltechTHESIS:10112017-143307471

Abstract

In order to measure the capture cross section of C¹³ at the lowest possible energy a scintillation detector in conjunction with a high current ion source was developed. Because of heat dissipation problems the ion source was pulsed and suitable electronic circuitry was developed to take advantage of the peak currents available. With this equipment it was found possible to obtain proton currents of one milliampere and a detection efficiency of eight percent.

At 128 kilovolts the capture cross section is,

σ = 5.0 ± 1.0 x 10^-33 cm²

Of the resulting radiation approximately eighty percent is 8 Mev in energy while the remaining is either a two or three step cascade with gamma ray energies between two and four million volts of energy.

In the equation,

σ = a/E e^{-b/E 1/2}

b = 5.96 Mev^1/2, and a = 10^-2 Mev barn.

Thesis Files