G. D. Gollin

Search for the decay KL→π0νν

This thesis describes a search for KL → πνν̄ decay, carried out as a part of E799-II experiment at Fermilab. Within the Standard Model, the KL → πνν̄ decay is dominated by the direct CP violating processes, and thus a discovery of the decay implies confirmation of the direct CP violation. Due to theoretically clean calculations, a measurement of Br(KL → πνν̄) is one of the best ways to determine the CKM parameter, and is one of the most sensitive probes for a new physics. No such events were observed, and we set an upper limit Br(KL → πνν̄) < 5.9× 10−7 , at the 90% confidence level. This result represents an improvement of a factor of 98 over the current limit listed by Particle Data Group, and of a factor of 3 over the recent preliminary result.

Drift Chamber System for a High Rate Experiment

A system of 19 large drift chambers has been built and used in an experiment in the FNAL muon beam. The design of the chambers and electronics enabled the system to perform with incident particle rates of up to 107 per second.

Measurement of the CP-violation parameter η+-γ in neutral kaon decays

Interference between [ital K][sub [ital S]] and [ital K][sub [ital L]] decays into the final state [pi][sup +][pi][sup [minus]][gamma] has been observed in experiment 731 at Fermilab. By fitting the distribution of decays downstream of a regenerator, a new CP-violation parameter [eta][sub +[minus][gamma]], analogous to [eta][sub +[minus]], has been measured, with its magnitude equal to (2.15[plus minus]0.26[plus minus]0.20)[times]10[sup [minus]3], and [phi][sub +[minus][gamma]], the associated phase angle, equal to (72[plus minus]23[plus minus]17)[degree]. Assuming that any difference between this fit value for [eta][sub +[minus][gamma]] and the previously measured value for [eta][sub +[minus]] can be attributed to direct CP violation in this decay, a limit of [vert bar][ital e][sub +[minus][gamma]][sup [prime]][vert bar]/[epsilon][lt]0.3 at the 90% confidence level has been made.

Experimental prospects in CP violation in K meson decay

Abstract Several experiments which are performing precision measurements of CP parameters in hopes of shedding new light on the origins of CP violation are discussed. Two are measuring the ratio |η00/η|, one is measuring η+-0, two experiments will measure the phase difference between η00 and η+-, and one will search for the decay KL → π0e+e−.

Experimental studies of CP violation in K meson decays through measurements of ε’/ε

Experimental evidence today is consistent with the dominant source of CP violation arising from a ..delta..S = 2 interaction which mixes K/sup 0/ and K-bar/sup 0/ in a time-asymmetric fashion. Fermilab experiment 731 and CERN experiment NA31 are performing precision measurements of the ratio /vert bar/eta/sub 00//eta/sub +//sub -//vert bar/ in hopes of shedding new light on the origins of CP violation. These two experiments are discussed.

Open and hidden charm muoproduction

New results are presented on open and hidden charm and bottom production by 209‐GeV muons interacting in a magnetized steel calorimeter. The upper limit on the production of T states by muons is σ(μN→TX)B(T→μμ)<22×10−39 cm2 (90% confidence level). The distributions of elastically produced ψ’s are consistent with s‐channel helicity conservation (SCHC) and disagree with ψ dominance. From analysis of dimuon final states the cross section for diffractive charm muoproduction is 6.9+1.9−1.4 nb. The structure function F2(cc) for diffractive charmed‐quark pair production is presented.

Limit on UPSILON muoproduction at 209 GeV

We present the dimuon mass spectrum from 102 678 three-muon final states produced by muon interactions within a magnetized steel calorimeter. The data place a 90%-confidence limit on the production of {Upsilon} states by muons: {sigma}({mu}N{yields}{mu}{Upsilon}X)B({Upsilon}{yields}{mu}{sup +}{mu}{sup -})<22x10{sup -39} cm{sup 2}, consistent with a photon-gluon-fusion model calculation.