The inclusive production rates of π±,K± andp\(\bar p\) inZ0 decays have been measured with the OPAL detector at LEP. Using the energy loss measurement in the jet chamber, the momentum range up to the beam energy (45.6 GeV/c) has been covered. Differential cross sections and total particle yields are given. Comparisons of the inclusive momentum spectra and the total rates with predictions of the JETSET and the HERWIG Monte Carlo model are presented. The total single rates are found to be 17.05±0.43 π±, 2.42±0.13K± and 0.92±0.11p\(\bar p\) per hadronic event. Predictions of JETSET for cross sections and total rates agree very well for π±; however, for momenta greater than 4 GeV/c,K± rates are underestimated and\(\bar p\) rates are overestimated. Combined with data of other particle species there is evidence that the peak positions in the ξ=ln(1/xp) distributions show a different mass dependence for mesons and baryons. However, both JETSET and HERWIG Monte Carlo predictions agree with the observed data.
Normalised momentum distribution for charged pion production.
Normalised momentum distribution for charged kaon production.
Normalised momentum distribution for proton / antiproton production.
The inclusive production cross sections and mean multiplicities of π±, K±, p, and p¯ in e+e− annihilation at a c.m. energy of 29 GeV have been measured with the time-projection chamber at PEP, using ionization energy loss to separate particle types. On average, 10.7±0.6 π±, 1.35±0.13 K±, and 0.60±0.08 p,p¯ are contained in an annihilation event. The fraction of pions among final-state particles decreases from over 95% at 0.3 GeV/c momentum to about 60% at high momentum; the kaon and proton fractions rise correspondingly.
PARTICLE FRACTIONS.
PARTICLE FRACTIONS.
PARTICLE FRACTIONS.
The inclusive charged-hadron momentum spectra from the ψ and ψ′ decays produced in e+e− collisions at SPEAR are presented. The data were obtained with a small solid-angle, single-arm magnetic spectrometer with good particle-identification abilities centered at 90 degrees with respect to the beams. The particle-separated invariant cross sections are compared with data from e+e− collisions at s=4.8 and 7.3 GeV, obtained with the same spectrometer, in order to observe the difference between hadron production at the resonances and in the continuum.
AT J/PSI.
AT J/PSI.
AT J/PSI.
We present results from a study of high-momentum inclusive hadron production in electron-positron interactions at s=3.8 and 4.8 GeV. Comparison of the momentum spectra at these energies shows no scaling violation in the region x(=EEbeam)>0.7. At s=4.8 GeV the Kπ ratio for hadrons with momenta >1.1 GeV/c is 0.27±0.08, and the average number of charged hadrons is 3.6±0.3 for those events which have at least one charged hadron with momentum greater than 1.1 GeV/c.
No description provided.
We report on inclusive hadron production in e+e− annihilation at 〈s〉=53 GeV2, using a small solid-angle magnetic spectrometer with good particle identification at 90° to the beams at SPEAR II. The cross sections of π± and K± when compared with data at s=23 GeV2 exhibit scaling in (sβ)dσdx with x=2Es12. The invariant cross section depends on the momentum as p−4.
No description provided.
No description provided.
No description provided.
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