Measurement of the relative partial decay rates for K+ -> pi+pi+pi-

A spark chamber experiment was performed at the Argonne National Laboratory Zero Gradient Synchrotron to measure the relative partial decay rates of positive and negative kaons decaying in the tau mode, K+ -> pi+pi+pi-. The ratio measured was If [equation] differs from unity» there is a CP violation in the weak process K+ -> (3pi)+/- due to the presence of parity conserving strangeness changing~6I ~ 5/2 transitions. Also strong final state pion interactions must be present. The experimental number measured was [equation] where ~ + was the number of tau decays observed and K+ was the number of kaons from which these tau decays occurred. The tau decays were observed by photographing the three pions in spark chambers. The kaons in a beam derived from the external proton beam were identified by a threshold and a differential gas Cerenkov counter. The film taken was scanned twice for taus. The identifying feature of a tau was three particles from a common vertex with no particle making an angle of greater than 100 with the direction of the decaying kaon. The two scans were checked frame by frame for conflicts in interpretations. These conflicts were resolved by scanners when feasible and by physicists. The value of [equation] observed was based on this reconciliation of the two scanso The sources of biases and the corrections to the relative rates, if any are discussed. The two corrections made to [equation] were due to the difference in K+ and K- transmissions through the beam defining counters and to accidentals. The corrections were +.0014 and -.0014, respectively The corrected value for the relative tau decay rates was [equation] The result is consistent with four interpretations. 1) There is no CP violation in K+ -> (3pi)+/- as seen in the relative tar: rates within the experimental error of 0.9%. 2) There are no final state pion interactions 3) There is a negligible I=3 contribution to the tau matrix element, 4) There are weak final state pion interactions and a small I=3 amplitude.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Year dc:date

2011

Author dc:creator

• Fletcher, Charles Roberts

Contributors dc:contributor

• Wattenberg, A.

• relative partial decay
• spark chamber experiment
• zero gradient synchrotron
• kaons

Statement dc:rights

• 1967 Charles Roberts Fletcher

Language dc:language

en

Identifier

6087838

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/25710