High density noble gas detectors and search for massive neutrinos in the [beta]-decay of [superscript 35] S

• Main Author: Imel, David A.
• Format: Others
• Language: en
• Published: 1990
• Online Access: https://thesis.library.caltech.edu/2594/1/Imel_da_1990.pdf; Imel, David A. (1990) High density noble gas detectors and search for massive neutrinos in the [beta]-decay of [superscript 35] S. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/5jsm-vs97. https://resolver.caltech.edu/CaltechETD:etd-06142007-091200 <https://resolver.caltech.edu/CaltechETD:etd-06142007-091200>

This thesis is divided into two parts. In Part I, I present a series of studies of high density noble gas detectors, the goal of which was to determine the feasibility of a [superscript 136] Xe [beta][beta]-decay detector. The limitations of liquid, high pressure and solid xenon and argon detectors are described in detail, and it is shown that initial recombination of [delta]-electrons provides the ultimate limit to energy resolution in the condensed media. Ionization spectra in solid xenon are presented for the first time. Part II describes an experiment which uses the Caltech iron-free double-focusing [beta]-spectrometer to test the possible admixture of a heavy neutrino in the [beta]-spectrum of [superscript 35] S. Preliminary data with a statistical uncertainty of 3x10(-3) are presented and show that the [beta]-spectrum is consistent with the allowed shape. Although the data are not accurate enough to verify or deny the existence of the 17 keV neutrino postulated by Simpson, data runs are underway which should clearly confirm it or rule it out.