A solid-state DE-E telescope beta spectrometer has been built and used to study beta-minus spectra. The system consists of a 15 mm x 500 mm$ sp2$ hyperpure germanium (HPGe) E-detector and a 300 $ mu$m x 200 mm$ sp2$ Si DE-detector with a special "keyhole" design. / The response function of the system has been determined experimentally using mono-energetic electron beams with incident energies ranging from 1 to 12 MeV. / The beta endpoint energies of 25 nuclei, namely, $ sp{32}$P, $ sp{88}$Rb, $ sp{91-99}$Rb, $ sp{91-96}$Sr, $ sp{99-100}$Sr, $ sp{92-96}$Y and $ sp{100}$Y have been measured. The Q-beta values and mass excesses for A = 91-100 have been determined. The results for $ sp{99}$Rb, $ sp{99-100}$Sr and $ sp{100}$Y have been obtained for the first time. / The beta strength functions for odd mass Rb isotopes, namely $ sp{91-99}$Rb have been measured for the first time from direct beta spectroscopy with a solid-state telescope system. The experimental results have been compared to calculations using the Brown-Bolsterli (B-B) model.

An accurate response function for a superconducting solenoid beta spectrometer for electrons up to 5.5 MeV has been found using Monte Carlo calculations and measurements of standard spectra. Experimental conditions affecting the response function have been studied and corrections for source scattering and pileup devised. / An anomalous shift in the electron energy calibration caused by the magnetic field has been discovered and explained. / The beta spectrum of ('32)P, ('90)Y, ('28)Al, ('42)K, ('38)Cl and ('88)Rb have been studied. Systematic uncertainties in endpoint, branch intensity and shape factor measurements have been estimated. / A beta spectra analysis program has been written to calculate endpoints, branch intensities and shape factors in a multi-branch spectrum. / The beta spectra of ('141)La, ('142)La, ('139)Ba, ('141)Ba, ('142)Ba, ('138)Cs and ('139)Cs have been studied. Q(,(beta))-values, intensities for all branches and some shape factors have been measured. / The shape factor of the ('20)F beta spectrum has been measured. The value found for the linear coefficient, a = 0.006 (+OR-) .002 (mc('2))('-1), supports the "weak magnetism" predictions of the Conserved Vector Current theory.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1964. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

A systematic study of the change in proton single-particle occupancies in two neutrinoless double beta decay candidates, 130Te to 130Xe and 136Xe to 136Ba, has been performed. Final states in 129Sb, 129I, 135I and 135Cs have been populated using the (d,3He) single proton removal reaction. The deuterons were accelerated to 101 MeV using the coupled azimuthally varying field and Ring cyclotrons at the Research Center for Nuclear Physics, University of Osaka. The outgoing ejectiles were momentum analysed using the Grand Raiden magnetic spectrometer. Absolute cross sections were measured for states up to 7 MeV in excitation. Transferred angular momenta were identified through a comparison of angular distributions with those calculated using the distorted-wave Born approximation. Spectroscopic factors were extracted from the experimental cross sections. In addition to the 0v2B decay candidates the reaction was also performed on 128Te, 132Xe, 134Xe and 138Ba as a consistency check. The occupancies of the nuclei were determined from the spectroscopic factors, the reaction model was normalised using a common normalisation factor across all targets. The change in occupancies between the 0v2B decay candidates and their daughters were then determined. The change in occupancies were then compared with those calculated by interacting shell model, interacting boson model and quasiparticle random phase approximation. This comparison showed that whilst the three theories were qualitatively able to reproduce the change in occupancies, quantitatively there are significant discrepancies. These are the same models that are used to determine the nuclear matrix elements governing the rate of 0v2B decay.

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<p> The energy levels of Sm151 populated in the beta decay of Pm151 have been studied with the aid of magnetic spectrometers. The internal and external conversion spectra were examined with a π√2 spectrometer of 50 cm radius. A Gerholm-type double lens coincidence spectrometer was used to perform electron-beta, electron-electron, electron-gamma and gamma-beta coincidence experiments. In addition, precise measurements of the transition energies obtained by Geiger and Graham (1962) with the Chalk River π√2 iron-free spectrometer are included. A decay scheme based on these results is proposed and speculations are made concerning the possible interpretation of the levels on the basis of the Nilsson model. The results are also compared with other recently published data on this decay.</p> / Thesis / Doctor of Philosophy (PhD)

Thirty-one excited levels in 153Eu and thirty-four in 155Eu have been located by means of the (3He,d) and beta decay reactions. The energies, intensities, and decay scheme classifications of forty-four gamma rays in 153Eu and fifty-two in 155Eu have been measured by means of singles and coincidence experiments using NaI and Ge(Li) detectors. Angular distribution studies of the reaction deuterons have been made a number of levels have neen assigned unique l values. An interpretation of the level schemes in terms of the Nilsson model have been attempted. / Thesis / Doctor of Philosophy (PhD)

<div> We consider the existence of a force that could produce a non-null result in the Eötvös experiment while producing a null result in the Eöt-Wash experiment. We introduce a general force, in the form of its Taylor series expansion, and determine the response of each experiment to that force. We can then determine which terms of the expansion are important to each experiment. A trial force, in the form of a mixed vector-scalar interaction is introduced and we analyze the resulting Eötvös parameters for various values of the strengths and ranges of the interactions. We find that under certain conditions the Eötvös parameter for the Eöt-Wash experiment can be made zero while the Eötvös parameter for the Eötvös experiment is nonzero.</div><div> </div><div><br></div><div> Next, we examine the possibility of a wind force appearing in the MICROSCOPE experiment. This wind would be due to the satellite's motion through a particle background which couples to the differential accelerometer through a baryon-number dependent interaction. We determine the signal that would be measured by MICROSCOPE satellite and compare the power spectrum density of this signal to the published power spectrum density of the experiment. </div><div> </div><div><br></div><div> Additionally, we present a new theoretical framework for the time-variation of nuclear decay rates. This new framework is motivated by the results of numerous experiments which show a periodicity of one year. The fractional decay rate of these experiments are constant, regardless of isotope. We find that a novel neutrino interaction, in the form of an index of refraction, successfully generates the constant fractional decay rates. Using the optical theorem and the relativistic Breit-Wigner distribution makes the index of refraction consistent with neutrino speed measurements. We conclude by describing other systems where the index of refraction could create observable oscillations.</div><div><br></div><div> </div><div> Finally, we consider the suppression of beta decay rates through the Pauli exclusion principle due to the presence of background cosmic and solar neutrinos. We derive the suppression factor for both thermalized and non-thermalized neutrinos.</div>