Contribution of CPLEAR to the physics of the neutral-kaon system

• Published in: Nuclear physics. A 1999-08, Vol.655 (1), p.c327-c336
• Main Authors: Weber, Peter, Angelopoulos, A., 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.A., Faravel, L., 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., Mandic, I., Manthos, N., Marel, G., Mikuz, M., Miller, J., Montanet, F., Muller, A., Nakada, T., Pagels, B., Papadopoulos, I., Pavlopoulos, P., Polivka, G., Rickenbach, R., Roberts, B.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: Article
• Language: English
• ISSN: 0375-9474
• DOI: 10.1016/S0375-9474(99)00221-3

We report the results of the CPLEAR experiment on CP-, T-, and CPT-symmetries in the neutral kaon system. CP-violation parameters are given for the K 0, K 0 → 2π, 3π decay channels. For the first time, T-violation is measured by a direct method using semileptonic decays. The CPT symmetry is tested through the parameters Im(δ) with a precision of 10 −5 and Re(δ) with a precision of a few 10 −4. With these two measurements, the difference in mass and width of K 0 and K 0 are bound to within 10 −18 GeV. In the limit of CPT invariance in the neutral kaon decays, the K 0 and K 0 masses are equal within 10 −19 GeV.