Date of Award

Summer 1957

Degree Type

Thesis - Restricted

Degree Name

Master of Science (MS)



First Advisor

Barkow, A. G.

Second Advisor

Freirich, L. W.

Third Advisor

Greene, J. B.


Four nuclear events were found in cosmic ray emulsion exposed at San Angelos, Texas, where the breakup of the primary is accompanied by a slow pion. They were systematically studied in order to understand the nature of the slow pion emission in the high energy breakup. Three of them can be represented as single nucleon-nucleon collision with the emission of a single slow pion. The fourth event accompanied by three slow pions appears to be due to the secondary inelastic scattering of high energy pions inside the heavy nucleus. In discussions with Professor Marcel Schein of the Physics Department at the University of Chicago, it was suggested that a study of these events may prove of value in determining the nature of nuclear excitation of the heavy nuclei due to collision with a single nucleon.