skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Limits on CP-invariance violation in K/sub. mu. 3/ decay

Thesis/Dissertation ·
OSTI ID:6146912

The component of muon polarization in K/sup +/ ..-->.. ..mu../sup +/ ..pi../sup 0/ nu decay normal to the decay plane has recently been measured at Brookhaven National Laboratory. The quantity vector sigma/sub ..mu../ (vector P/sub ..pi../ x vector P/sub ..mu../ is odd under time reversal and a finite expectation value for this quantity would constitute a violation of time reversal invariance or, using the CPT theorem, CP invariance. A 4 GeV positive non-separated beam was used as a source of kaons. The decay plane of the kaon was defined by a photon from the pion decay detected in a lead glass array placed on the beam axis and the azimuthal angle of the muon measured by scintillation counter hodoscopes. The muons were brought to rest in an aluminum polarimeter where they precessed in a 55 gauss magnetic field. The spin direction of the muon was measured by the asymmetry in the detection of the positron from the decay ..mu../sup +/ ..-->.. e/sup +/ nu/sub e/anti nu/sub ..mu../. Twenty million events were collected and analyzed. The transverse polarization was measured to be 6.09 +- 0.029. 10/sup -1/ and the polarization normal to the decay plane, the CP violating component, was 0.0036 +- 0.0046 with the largest contribution to the uncertainty coming from the statistical error. The cylindrically symmetric detector reduced the systematic error to a negligible level. From the two polarization measurements we can place a limit on lm Xi, where Xi is the ratio of form factors describing K/sub ..mu..3/ decay, of 0.018 +- 0.024.

Research Organization:
Yale Univ., New Haven, CT (USA)
OSTI ID:
6146912
Resource Relation:
Other Information: Thesis (Ph. D.)
Country of Publication:
United States
Language:
English