Determination of P(c -> D*(+)) and BR(c -> l(+)) at LEP 1

The probability P(c → D*+) that a charm quark fragments into a D*+ meson and the c → l+ semileptonic branching fraction were measured in Z0 decay into cc̄ events. From the analysis of 3.5 Million Z0 events collected from 1992 to 1995, a sample of charm meson decays with 81% cc̄ purity was selected....

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Bibliographic Details
Main Authors: Abreu, P, Adam, W, Adye, T, Adzic, P, Ajinenko, I, Albrecht, Z, Alderweireld, T, Alekseev, G, Alemany, R, Allmendinger, T, Allport, P, Almehed, S, Amaldi, U, Amapane, N, Amato, S, Anassontzis, E, Andersson, P, Andreazza, A, Andringa, S, Antilogus, P, Apel, W, Arnoud, Y, Asman, B, Augustin, J, Augustinus, A
Format: Journal article
Language:English
Published: 2000
Description
Summary:The probability P(c → D*+) that a charm quark fragments into a D*+ meson and the c → l+ semileptonic branching fraction were measured in Z0 decay into cc̄ events. From the analysis of 3.5 Million Z0 events collected from 1992 to 1995, a sample of charm meson decays with 81% cc̄ purity was selected. The product of the c → D*+ fragmentation probability times the D*+ → D0π+ branching fraction was measured to be: P(c → D*+) · BR(D*+ → D0π+) = 0.174 ± 0.010(stat) ± 0.004(syst). Using the world averaged value for BR(D*+ → D0π+), the fragmentation probability is inferred: P(c → D*+) = 0.255 ± 0.015(stat) ± 0.006(syst) ± 0.005(syst.BR). From the same sample, 1828 ± 51 identified leptons in the opposite hemisphere were selected. From this sample, the charm semileptonic branching fraction was measured to be: BR(c → l+) = 0.0958 ± 0.0042(stat) ± 0.0028(syst).