Measurements are reported of inclusivef2(1270) andf0(975) production in γp, π±p andK±p collisions at photon beam energies of 65 to 175 GeV and hadron beam energies of 80 and 140 GeV. Thef2 andf0 mesons were found at masses of 1.250 GeV and 0.961 GeV respectively. Inclusivef2 production at lowxF was found to have a similarpT dependence for each beam type, whereas an additional pion-exchange contribution was found for production by pions at highxF. Cross sections are compared with those for ρ0 production and give no indication of a non-q\(\bar q\) component in eitherf-meson state.
No description provided.
No description provided.
No description provided.
The antiproton-proton small-angle elastic-scattering distribution was measured at\(\sqrt s \) GeV at the Fermilab Tevatron Collider. A fit to the nuclear-scattering distribution in the range 0.065≤|t|≤0.21 (GeV/c)2 givesb=(16.2±0.5±0.5) (GeV/c)−2 for the logarithmic slope parameter. Using the optical theorem and the luminosity from Collider parameters, we obtain σtoto(1+ρ2)1/2 =(61.7±3.7±4.4)mb.
No description provided.
Cross sections derived assuming RE(AMP)/IM(AMP) = 0.140, see Phys. Lett. B188, 143 (1987).
Slope was derived in the t range -0.065 < t < -0.21 (GeV/c)**2.
Measurements are presented of the inclusive distributions of theJ/Ψ meson produced by muons of energy 200 GeV from an ammonia target. The gluon distribution of the nucleon has been derived from the data in the range 0.04
Data are normalized to total cross section of 36 nb (not corrected for coherence).
Data are normalized to total cross section of 36 nb (not corrected for coherence).
Data are normalized to total cross section of 36 nb (not corrected for coherence).
Results are presented on the ratios of the nucleon structure function in copper to deuterium from two separate experiments. The data confirm that the nucleon structure function,F2, is different for bound nucleons than for the quasi-free ones in the deuteron. The redistribution in the fraction of the nucleon's momentum carried by quarks is investigated and it is found that the data are compatible with no integral loss of quark momenta due to nuclear effects.
Results from the 'chariot' experiment.
Results from the 'addendum' experiment.
Merged 'chariot' and 'addendum' ratio.. Errors are combined statistics and systematics.
Based on an analysis of the extensive air shower data accumulated over the last ten years at Akeno Cosmic Ray Observatory, the value of the proton-air nuclei inelastic cross section (σinp−air) has been determined assuming the validity of quasi-Feynman scaling of particle production in the fragmentation region. The energy dependence of σinp−air can be represented as 290(E/1 TeV)0.052 mb in the energy interval 1016.2–1017.6 eV, where E is the incident proton energy. The total p-p cross section (σtotp−p), derived using the nuclear distribution function obtained from the shell model, increases with energy as 38.5+1.37 ln2(√s /10 GeV) mb.
No description provided.
Best fit to data gives SIG(PP) = 38.5 + 1.37*LN(SQRT(S)/10 GeV)**2.
Cross sections for the reaction pp¯→e+e− have been measured at s=8.9,12.4, and 13.0 GeV2. The cross sections have been analyzed to obtain the proton electromagnetic form factors in the timelike region. We find that GM(q2)∝q−4αs2(q2) for q2≥5 (GeV/c)2.
No description provided.
No description provided.
No description provided.
The total photoproduction cross section is determined from a measurement of electroproduction with the ZEUS detector at HERA. The Q 2 values of the virtual photons are in the range 10 −7 < Q 2 <2×10 −2 GeV 2 . The γp total cross section in the γp centre of mass energy range 186–233 GeV is 154 ± 16 (stat.) ± 32 (syst.) μ b.
Scattered electron in range 10 to 16 GeV.
Using the 18.8 pb −1 of data accumulated at LEP in 1990 and 1991 with the ALEPH detector, a direct test of neutral current CP -invariance is performed by a search for CP -odd correlations in Z decays to τ pairs where both τ decay modes are identified. No evidence for CP -violation is observed. The weak dipole moment of the τ has been measured to be d τ ( m Z ) = (1.3 ± 1.4 ± 0.1) × 10 −17 e ·cm which results in an upper limit on the weak dipole moment of | d τ ( m Z )| ⩽ 3.7 × 10 −17 e ·cm with 95% confidence level.
No description provided.
Multiplicity distributions of negatively charged particles have been studied in restricted phase space intervals for central S+S, O+Au and S+Au collisions at 200 GeV/nucleon. It is shown that multiplicity distributions are well described by a negative binomial form irrespectively of the size and dimensionality of phase space domain. A clan structure analysis reveals interesting similarities between complex nuclear collisions and a simple partonic shower. The lognormal distribution agrees reasonably well with the multiplicity data in large domains, but fails in the case of small intervals. No universal scaling function was found to describe the shape of multiplicity distributions in phase space intervals of varying size.
Multiplicity distribution analysed in 1D for M = 4.
Multiplicity distribution analysed in 2D for M = 16.
Multiplicity distribution analysed in 3D for M = 64.
Production of charged kaons in proton-sulphur, proton-gold, sulphur-sulphur and oxygen-gold collisions at 200 GeV/nucleon has been studied in the NA35 Streamer Chamber experiment. Rapidity and transverse mass distributions as well as mean multiplicities were obtained. The results are compared with nucleon-nucleon data and with model predictions.
Tranverse mass distribution for all charged kaons in S S collisions for the limited yrap range 1.4 to 2.4.
Tranverse mass distribution for K0S production in the limited rapidity range 1.4 to 2.4. Data are taken from Bartke et al. ZP C48 (1990) 191.
Rapidity distribution for K+ production in p SU interactions.
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