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Title: Measurement of the parity nonconserving neutral weak interaction in atomic thallium

Abstract

This thesis describes an experiment to measure parity nonconservation in atomic thallium. A frequency doubled, flashlamp pumped tunable dye laser is used to excite the 6P/sub 1/2/(F = 0) ..-->.. 7P/sub 1/2/(F = 1) transition at 292.7 nm, with circularly polarized light. An electrostatic field E of 100 to 300 V/cm causes this transition to occur via Stark induced electric dipole. Two field free transitions may also occur: a highly forbidden magnetic dipole M, and a parity nonconserving electric dipole epsilon/sub P/. The latter is presumed to be due to the presence of a weak neutral current interaction between the 6p valence electron and the nucleus, as predicted by gauge theories which unite the electromagnetic and weak interactions. Both M and epsilon/sub P/ interfere with the Stark amplitude ..beta..E to produce a polarization of the 7P/sub 1/2/ state. This is measured with a circularly polarized infrared laser beam probe, tuned to the 7P/sub 1/2/ ..-->.. 8S/sub 1/2/ transition. This selectively excites m/sub F/ = +1 or -1 components of the 7P/sub 1/2/ state, and the polarization is seen as an asymmetry in 8S ..-->.. 6P/sub 3/2/ fluorescence when the probe helicity is reversed. The polarization due to M is ..delta../submore » M/ = -2M/(BETAE). It is used to calibrate the analyzing efficiency. The polarization due to epsilon/sub P/ is ..delta../sub P/ = 2i epsilon/sub P//(..beta..E), and can be distinguished from ..delta../sub M/ by its properties under reversal of the 292.7 nm photon helicity and reversal of the laser direction. A preliminary measurement yielded a parity violation in agreement with the gauge theory of Weinberg and Salam.« less

Authors:
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
OSTI Identifier:
6756580
Report Number(s):
LBL-11641
TRN: 81-002326
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Technical Report
Resource Relation:
Other Information: Thesis
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; THALLIUM; WEAK INTERACTIONS; P INVARIANCE; ENERGY-LEVEL TRANSITIONS; EXPERIMENTAL DATA; FLUORESCENCE; GAUGE INVARIANCE; STARK EFFECT; WEAK NEUTRAL CURRENTS; ALGEBRAIC CURRENTS; BASIC INTERACTIONS; CURRENTS; DATA; ELEMENTS; INFORMATION; INTERACTIONS; INVARIANCE PRINCIPLES; LUMINESCENCE; METALS; NEUTRAL CURRENTS; NUMERICAL DATA; 645102* - High Energy Physics- Particle Interactions & Properties-Experimental- Weak Interactions & Properties

Citation Formats

Bucksbaum, P H. Measurement of the parity nonconserving neutral weak interaction in atomic thallium. United States: N. p., 1980. Web. doi:10.2172/6756580.
Bucksbaum, P H. Measurement of the parity nonconserving neutral weak interaction in atomic thallium. United States. https://doi.org/10.2172/6756580
Bucksbaum, P H. 1980. "Measurement of the parity nonconserving neutral weak interaction in atomic thallium". United States. https://doi.org/10.2172/6756580. https://www.osti.gov/servlets/purl/6756580.
@article{osti_6756580,
title = {Measurement of the parity nonconserving neutral weak interaction in atomic thallium},
author = {Bucksbaum, P H},
abstractNote = {This thesis describes an experiment to measure parity nonconservation in atomic thallium. A frequency doubled, flashlamp pumped tunable dye laser is used to excite the 6P/sub 1/2/(F = 0) ..-->.. 7P/sub 1/2/(F = 1) transition at 292.7 nm, with circularly polarized light. An electrostatic field E of 100 to 300 V/cm causes this transition to occur via Stark induced electric dipole. Two field free transitions may also occur: a highly forbidden magnetic dipole M, and a parity nonconserving electric dipole epsilon/sub P/. The latter is presumed to be due to the presence of a weak neutral current interaction between the 6p valence electron and the nucleus, as predicted by gauge theories which unite the electromagnetic and weak interactions. Both M and epsilon/sub P/ interfere with the Stark amplitude ..beta..E to produce a polarization of the 7P/sub 1/2/ state. This is measured with a circularly polarized infrared laser beam probe, tuned to the 7P/sub 1/2/ ..-->.. 8S/sub 1/2/ transition. This selectively excites m/sub F/ = +1 or -1 components of the 7P/sub 1/2/ state, and the polarization is seen as an asymmetry in 8S ..-->.. 6P/sub 3/2/ fluorescence when the probe helicity is reversed. The polarization due to M is ..delta../sub M/ = -2M/(BETAE). It is used to calibrate the analyzing efficiency. The polarization due to epsilon/sub P/ is ..delta../sub P/ = 2i epsilon/sub P//(..beta..E), and can be distinguished from ..delta../sub M/ by its properties under reversal of the 292.7 nm photon helicity and reversal of the laser direction. A preliminary measurement yielded a parity violation in agreement with the gauge theory of Weinberg and Salam.},
doi = {10.2172/6756580},
url = {https://www.osti.gov/biblio/6756580}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Nov 01 00:00:00 EST 1980},
month = {Sat Nov 01 00:00:00 EST 1980}
}