Determination of the T- and CPT-violation parameters in the neutral-kaon system using the Bell–Steinberger relation and data from CPLEAR

Data from the CPLEAR experiment, together with the most recent world averages for some of the neutral-kaon parameters, were constrained with the Bell-Steinberger (or unitarity) relation, allowing the T-violation parameter Re(epsilon) and the CPT-violation parameter Im(delta) of the neutral-kaon mixing matrix to be determined with an increased accuracy: Re(epsilon)=(164.9 +/- 2.5) x 10(-5), Im(delta)=(2.4 +/- 5.0) x 10(-5). Moreover, the constraint allows the CM-violation parameter for the neutral-kaon semileptonic decays, Re(), to be determined for the first time. The Delta S not equal Delta Q parameters Re(x_) and Im(x(+)) are given with an increased accuracy. The quantity Re(y + x_), which enters the T-violation CPLEAR asymmetry previously published, is determined to be (- 0.2 +/- 0.3) x 10(-3). The value obtained for Re(delta) is in agreement with the one resulting from a previous unconstrained fit and has a slightly smaller error. (C) 1999 Elsevier Science B.V, All rights reserved.