The charged-particle fractional momentum distribution within jets, D(z), has been measured in dijet events from 1.8-TeV p¯p collisions in the Collider Detector at Fermilab. As expected from scale breaking in quantum chromodynamics, the fragmentation function D(z) falls more steeply as dijet invariant mass increases from 60 to 200 GeV/c2. The average fraction of the jet momentum carried by charged particles is 0.65±0.02(stat)±0.08(syst).
No description provided.
We present measurements of the pseudorapidity (η) distribution of charged particles (dNchdη) produced within |η|≤3.5 in proton-antiproton collisions at s of 630 and 1800 GeV. We measure dNchdη at η=0 to be 3.18±0.06(stat)±0.10(syst) at 630 GeV, and 3.95±0.03 (stat)±0.13(syst) at 1800 GeV. Many systematic errors in the ratio of dNchdη at the two energies cancel, and we measure 1.26±0.01±0.04 for the ratio of dNchdη at 1800 GeV to that at 630 GeV within |η|≤3. Comparing to lower-energy data, we observe an increase faster than ln(s) in dNchdη at η=0.
General rapidity densities.
No description provided.
Differential pseudorapidity distribution.. The numbers here at 1800 GeV have been taken from the HZTool routine hzf89201e provded by Arthur Moraes.
We have observed hadronic final states produced in the decays of Z bosons. In order to study the parton structure of these events, we compare the distributions in sphericity, thurst, aplanarity, and number of jets to the predictions of several QCD-based models and to data from lower energies. The data and models agree within the present statistical precision.
Corrected event shape distributions.
Corrected event shape distributions.
Corrected event shape distributions.
Measurements of inclusive transverse-momentum spectra for KS0 mesons produced in proton-antiproton collisions at s of 630 and 1800 GeV are presented and compared with data taken at lower energies. The ratio, as a function of pT, of the cross section for KS0 to that for charged hadrons is very similar to what is observed at lower energies. At 1800 GeV, we calculate the strangeness-suppression factor λ=0.40±0.05.
Estimated effective cross sections for events which pass the trigger and selection criteria. The uncertainties in these represent the principal source of error in the overall normalisation of the results.
Statistical errors only.
Statistical errors only.
We report evidence for the production of the charged D ∗ mesons in pp̄ collisions at s = 540 GeV . The search was confined to the charged particle fragments of hadronic jets, which are expected to be predominantly gluon jets in this experiment. The fragmentation function and production rate for D ∗ in jets of average transverse momentum of 28 GeV/ c are given.
THE D*'S ARE CONSIDERED AS ARISING ONLY FROM FRAGMENTATION OF HADRONIC JETS ('GLUON' JETS). HERE THE <PT> OF THE JET IS AROUND 28 GEV THE DEFINITION OF Z IS P(D*).P(JET)/(P(JET))**2.
Results on charged particle production in pp̄ collision at s 1 2 = 540 GeV are presented. The data were obtained at the CERN pp̄ collider using the UA1 detector, operated without magnetic field. The central particle density is 3.3 + - 0.2 per unit o pseudo-rapidity for non-diffractive events. KNO scaling of the multiplicity distributions withresults from ISR energies is observed.
Pseudorapidity density distribution for all charged multiplicities corrected for acceptance and backgrounds by excluding NSD events. Data have been read from the plot.
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