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

• Published in: Physics letters. B Vol. 456; no. 2; pp. 297 - 303
• Main Authors: Apostolakis, A., Aslanides, E., Backenstoss, G., Bargassa, P., Behnke, O., Benelli, A., Bertin, V., Blanc, F., Bloch, P., Carlson, P., Carroll, M., Cawley, E., Chertok, M.B., Danielsson, M., Dejardin, M., Derre, J., Ealet, A., Eleftheriadis, C., Fetscher, W., Fidecaro, M., Filipčič, A., Francis, D., Fry, J., Gabathuler, E., Gamet, R., Gerber, H.-J., Go, A., Haselden, A., Hayman, P.J., Henry-Couannier, F., Hollander, R.W., Jon-And, K., Kettle, P.-R., Kokkas, P., Kreuger, R., Le Gac, R., Leimgruber, F., Mandić, I., Manthos, N., Marel, G., Mikuž, M., Miller, J., Montanet, F., Muller, A., Nakada, T., Pagels, B., Papadopoulos, I., Pavlopoulos, P., Polivka, G., Rickenbach, R., Roberts, B.L., Sakeliou, L., Ruf, T., Schäfer, M., Schaller, L.A., Schietinger, T., Schopper, A., Tauscher, L., Thibault, C., Touchard, F., Touramanis, C., Van Eijk, C.W.E., Vlachos, S., Weber, P., Wigger, O., Wolter, M., Zavrtanik, D., Zimmerman, D.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1999; Elsevier
• Subjects: High Energy Physics - Experiment; Physics
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/S0370-2693(99)00483-9

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( ϵ) and the CPT-violation parameter Im( δ) of the neutral-kaon mixing matrix to be determined with an increased accuracy: Re( ϵ)=(164.9±2.5)×10 −5, Im( δ)=(2.4±5.0)×10 −5. Moreover, the constraint allows the CPT-violation parameter for the neutral-kaon semileptonic decays, Re( y), to be determined for the first time. The ΔS≠ ΔQ 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)×10 −3. The value obtained for Re( δ) is in agreement with the one resulting from a previous unconstrained fit and has a slightly smaller error.