A Study of the Gamma Radiation Produced in the Alpha-Particle Bombardment of 0¹⁶

Author: Pearson, John Davie

Year: 1963

Degree: Dissertation (Ph.D.)

Advisors: Lauritsen, Thomas; Fowler, William A.; Barnes, Charles A.; Kavanagh, Ralph William

Committee Member: Unknown, Unknown

Option: Physics

DOI: 10.7907/EYG1-JW84

Abstract

This thesis describes an investigation of gamma rays from the reaction O^(16)(α,γ)Ne^(20). The excitation function for gamma radiation has been studied for laboratory alpha-particle energies E_α from 4.8 to 9.9 Mev. Resonances were observed at E_α = 5.374, 5.94, 6.61, 6.930, 7.94, 8.17, 8.54, and 9.40 Mev, corresponding to Ne^(20) states at excitation energies of 9.029, 9.48, 10.02, 10.270, 11.08, 11.27, 11.56, and 12.25 Mev. Gamma-ray angular distribution measurements establish spins and parities of 4^+, 2^+, and 4^+ for the 9.029.-, 10270-, and 11.08-Mev states respectively. The 2^+ assignment for the 10.270-Mev state is supported by the results of triple angular-correlation studies made on the gamma-ray cascade from this state. Decay schemes have been investigated and estimates made of radiative widths and total widths. It is concluded that the 10.270-Mev state is the first T = 1 state of Ne^(20) on the basis of measurements of its excitation energy, spin and parity, total width, and M1 radiative width. The excitation function for 6.13-Mev gamma rays from the reaction O^(16)(α, α'γ)O^(16) has been studied for E_α from 8.9 to 9.9 Mev. The data indicates a resonance at E_α = 9.57 Mev corresponding to a state in Ne^(20) at 12.39 Mev. There is some evidence for a weaker resonance at E_α = 9.25 Mev corresponding to a state at 12.13 Mev.

Files