A search for parity non-conservation in polarized proton-nucleon scattering at 6 GEV/C

An experiment has been performed at the Argonne National Laboratory Zero Gradient Synchrotron to measure the dependence of the total proton-nucleon cross section on the helicity of the incident proton. A dependence of the total cross section on the proton helicity is a measure of the strength of the weak interaction in the hadronic system. The cross section was determined by measuring the transmission of 6 GeVlc polarized (-26.3 ± 7.5) 10 where 0 (0) is the total section for positive protons through an H20 target. integral counting techniques were used to achieve the high data rates required for the measurement of the small effect. We measured the cross section asymmetry (sigma+ - sigma_)/(sigma+ + sigma_) = (-26.3 +- 7.5) x 10-5 where sigma+ (sigma_) is the total cross section for positive (negative) helicity protons incident on an H20 target. The asymmetry is substantially larger than predicted by conventional theories of the weak interaction. Systematic contributions to the asymmetry are discussed. This result may include systematic contributions which were not measured or were measured Inadequately by our apparatus. Suggestions for improving the experiment are made. Preliminary results for the asymmetry from the improved version of the experiment are given which are consistent with zero.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Year dc:date

2011

Author dc:creator

• Alde, Douglas Marshall

Contributors dc:contributor

• Frauenfelder, Hans

• parity non-conservation
• polarized proton-nucleon scattering
• incident proton helicity
• hadronic system

Statement dc:rights

• 1979 Douglas Marshall Alde

Language dc:language

en

Identifier

397402

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/25550