AGS Proposal 923

Search for T-Violating Muon Polarization

in the Kmu3 Decay

We propose a new search for the time reversal violating polarization of the muon normal to the decay plane of the decay. The value of such a polarization in the Standard Model is zero. However, it is now accepted that the baryon asymmetry of the universe requires a source of CP violation stronger than that embodied in the quark mixing matrix. Models of non-standard CP violation that produce the baryon asymmetry could also produce effects observable in the transverse polarization. Moreover, because of the very high sensitivity of the experiment the possibility of discovering unexpected new physics should not be underestimated. The experiment will be performed with in-flight decays in an intense ( per sec) 2 GeV/c separated kaon beam in an existing beam-line at the AGS. The center piece of the detector will be a new polarimeter which will consist of 128 carbon wedges, with active detector elements (either scintillator or wire chambers) between the wedges, arranged in a cylindrical manner around the kaon beam. We expect to analyze more than events to obtain sensitivity to the T-violating polarization of at 1 sigma, corresponding to the sensitivity of to , an improvement by approximately 40 over the previous best limit.

Beam: 2.0 GeV/c Separated K+ Beam 2.0x10^7 per AGS Pulse

Detector: Plastic Scintillator, Pb-scintillator calorimeter, Fe shield, Graphite Polarimeter, Muon Chambers

Flux Requested: 2x10^6 AGS pulses at 30x10^12 Protons/pulse. Approx 2000 hrs of running.

Robert Adair, Yale University, adair@yalph2.physics.yale.edu

Milind V. Diwan, Brookhaven National Laboratory, diwan@bnl.gov

Hong Ma, Brookhaven National Laboratory, hma@bnl.gov

• A. Carroll, M.V. Diwan, J. Frank, A. Gordeev, S. Kettell, L. Leipuner, L. Littenberg, Hong. Ma, V. Polychronakos
  • Brookhaven National Laboratory, Long Island, NY
    

• G. Atoyan, Y. Andreev, V. Issakov, O. Karavichev, T. Karavisheva, A. Poblaguev, A. Proskuryakov
  • Institute for Nuclear Research, Moscow, Russia
    

• V. Semenov
  • Institute for High Energy Physics, Protvino, Russia
    

• M. Elaasar, D. Greenwood, K. Johnston
  • Louisiana Tech University, Rustom, LA
    

• R. Adair , R. Larson
  • Yale University, New Haven, CT