The excitation function for the reaction ⁵⁶F(p,y)⁵⁷Co has been measured from 1200 - 3000 KeV proton energy using enriched ⁵⁶Fe targets. Gamma-ray spectra were measured using Ge(Li) and NaI(T£) detectors. The resonance strength, 10^, has been determined for the studied resonances. Gamma-ray angular distributions were measured using NaI(T£) detectors. In the energy region between 1240 and 1272 KeV, the gamma-ray angular distributions were measured using the Ge(Li) detector. Gamma-ray angular distributions have been measured for resonances corresponding to excitation energies in ⁵⁷Co of 7253, 7267, 7272, 7598, 7622, 7641, 7647, 7925, 8192 and 8450 KeV. The-branching ratios, spins and parities of the resonance levels as well as some of the low-lying states in ⁵⁷Co have been established. The reaction Q-value derived from these measurements is Q = 6027 ± 3 KeV. From the gamma-ray spectra and angular distributions which have been studied the levels at 7253, 7267 and 7272 KeV excitation in ⁵⁷Co are identified as the split analogue of the T = 5/2 corresponding to the first bound state in the parent nucleus ⁵⁷Fe at 14 KeV. The group of levels at 7622, 7641 and 7647 KeV excitation in ⁵⁷Co are believed to form the split analogue of the 367 KeV bound state in 57Fe. The level at 8450 KeV excitation is tentatively identified as the isobaric analogue state of T = 5/2 corresponding to the 1196 KeV bound state in ⁵⁷Fe. The absence of the isobaric analogue resonance corresponding to the ground state in ⁵⁷Fe is discussed as a result of the present study. A coulomb displacement energy for ⁵⁷Co - ⁵⁷Fe of 8876 ± 6 KeV is deduced from these measurements. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

The E2 cross section for the ¹²C(p,Ύ₀)¹³N reaction has been measured from 10 MeV to 17 MeV in the laboratory system by bombarding an enriched carbon-12 target with beams of polarized protons. A 10 in. φ x 10 in, Nal(Tl) detector with a plastic anti-coincidence shield was used to detect the gamma rays. The total E2 capture cross sections were of the order of 0.2 ybarns and no resonance effects were observed. The amount of the E2 energy-weighted sum rule depleted in this energy range is (10.3 ± 4.0)%. Calculations based on a direct semi-direct capture model provide a good description of the experimental results by including only direct E2 capture and direct plus collective E1 capture. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Graduation date: 1992

No description available.

The suitability of using a Nal crystal as a fast coincidence gamma ray detector was investigated using the multichannel "fast-slow" delayed coincidence method to obtain prompt time resolution curves with a Na²² gamma ray source at Nal temperatures of 170, 185, 200°K. A comparison of the time resolution curve obtained using two NE 102 plastic scintillators (FWHM: 640 psec) with that using a cooled Nal scintillator and a NE 102 scintillator (FWHM: 680-psee) showed that Nal is a satisfactory fast coincidence gamma ray detector at 185°K. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

No description available.

Call number: LD2668 .T4 1963 F69 / Master of Science

Call number: LD2668 .T4 1965 M32 / Master of Science

Thesis (Ph. D.)--University of Wisconsin--Madison, 1977. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 59).

A cryostat has been built for cooling specimens to temperatures of the order of a hundredth of a Kelvin by thermal contact with an adiabatically demagnetized paramagnetic salt pill. The apparatus was designed for performing nuclear orientation experiments. This thesis describes the construction of the apparatus and experimental tests studying the nuclear orientation of (60)Co in an iron plate. The paramagnetic salt used was chromium potassium alum in an alum-glycerine slurry. In addition to the chrome alum pill a guard pill of manganous ammonium sulphate was used between the alum pill and the 1K helium bath. The pills were supported and thermally isolated by German silver spacers. A copper heat link was embedded in the alum-glycerine slurry and soldered to the specimen to provide thermal contact. Several heat links were used ranging from a bundle of five thousand copper wires to a copper foil "concertina" arrangement. A Ventron niobium-titanium superconducting solenoid which produced fields up to 48 kilogauss was used for the magnetic cooling. A superconducting polarizing solenoid was used to magnetically saturate the polycrystalline iron plate. Anisotropies in the gamma radiation intensity from (60)Co of 7 to 11 per cent corresponding to temperatures of 37 to 45 m K were observed. / Science, Faculty of / Physics and Astronomy, Department of / Graduate