TY - JOUR

T1 - Production of charmed mesons in Z decays

AU - Buskulic, D.

AU - Finch, Alexander

AU - ALEPH Collaboration

PY - 1994

Y1 - 1994

N2 - The production of charmed mesons D0(−) ,D ± , andD *± is studied in a sample of 478,000 hadronicZ decays. The production rates are measured to be Γ(Z→D∗±X)Γhad=0.187±0.015(exp.)±0.013(BR),\hfillΓ(Z→D±X)Γhad=0.251±0.026(exp.)±0.025(BR),\hfillΓ(Z→D0(−)X)Γhad=0.518±0.052(exp.)±0.035(BR),\hfill where the errors from this analysis are separated from those coming from theD branching ratios (BR). TheD *± momentum distribution is extracted separately for Z→ccˉ and Z→bbˉ events with the help of event shape variables. It is consistent with the prediction of the JETSET Monte Carlo program after adjustment of the charm fragmentation function. Constraining the shape of the Z→bbˉ contribution, the average fraction of the beam energy taken by aD * meson produced in the fragmentation of a charm quark is extracted by a parametric fit to be <X E > c =0.495±0.011±0.007. Evidence forD **0 (D 1(2420)0 and/orD 2 *(2460)0) production is found in the D∗±π∓ channel, accounting for a fraction (18±5±2)% of allD *± production. The relative production of vector and pseudoscalar mesons is dicussed, together with the possible effects ofD ** production. Thec-quark forward-backwardZ-pole asymmetry is detrmined from that of high momentumD *± to beA FB 0,c =(7.7±4.4)%.

AB - The production of charmed mesons D0(−) ,D ± , andD *± is studied in a sample of 478,000 hadronicZ decays. The production rates are measured to be Γ(Z→D∗±X)Γhad=0.187±0.015(exp.)±0.013(BR),\hfillΓ(Z→D±X)Γhad=0.251±0.026(exp.)±0.025(BR),\hfillΓ(Z→D0(−)X)Γhad=0.518±0.052(exp.)±0.035(BR),\hfill where the errors from this analysis are separated from those coming from theD branching ratios (BR). TheD *± momentum distribution is extracted separately for Z→ccˉ and Z→bbˉ events with the help of event shape variables. It is consistent with the prediction of the JETSET Monte Carlo program after adjustment of the charm fragmentation function. Constraining the shape of the Z→bbˉ contribution, the average fraction of the beam energy taken by aD * meson produced in the fragmentation of a charm quark is extracted by a parametric fit to be <X E > c =0.495±0.011±0.007. Evidence forD **0 (D 1(2420)0 and/orD 2 *(2460)0) production is found in the D∗±π∓ channel, accounting for a fraction (18±5±2)% of allD *± production. The relative production of vector and pseudoscalar mesons is dicussed, together with the possible effects ofD ** production. Thec-quark forward-backwardZ-pole asymmetry is detrmined from that of high momentumD *± to beA FB 0,c =(7.7±4.4)%.

U2 - 10.1007/BF01559519

DO - 10.1007/BF01559519

M3 - Journal article

VL - 62

SP - 1

EP - 14

JO - Zeitschrift für Physik C Particles and Fields

JF - Zeitschrift für Physik C Particles and Fields

SN - 0170-9739

IS - 1

ER -