Precise determination of the lifetime of the charmed baryon Λ c

• Published in: Physics letters. B 1989-02, Vol.218 (3), p.374-380
• Main Authors: Barlag, S., Becker, H., Böhringer, T., Bosman, M., Castillo, V., Chabaud, V., Damerell, C., Daum, C., Dietl, H., Gillman, A., Gilmore, R., Gooch, T., Görlich, L., Gras, P., Hajduk, Z., Higon, E., Kelsey, D.P., Klanner, R., Kwan, S., Lücking, B., Lütjens, G., Lüth, V., Lutz, G., Malos, J., Männer, W., Neugebauer, E., Palka, H., Pepé, M., Richardson, J., Rybicki, K., Seebrunner, H.J., Stierlin, U., Tiecke, H.G., Waltermann, G., Watts, S., Weilhammer, P., Wickens, F., Wiggers, L.W., Witek, M., Zeludziewicz, T.
• Format: Article
• Language: English
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/0370-2693(89)91600-6

We present the final result on the measurement of the lifetime of the Λ c-baryon from a sample of Λ c-decays obtained in the NA32 experiment at the CERN SPS using silicon microstrip detectors and charge-coupled devices for vertex reconstruction. We observe a total of 160 Λ c in five different decay modes. A sample of 101 unambiguous decays of Λ c→pK − π + (and charge conjugate) above a background of 7 events is used for the Λ c mass and lifetime measurement. The mean Λ c lifetime is determined to be 1.96 −0.20 +0.23×10 −13s and the Λ c mass to be 2285.8±0.6±1.2 MeV/ c 2.