Results are given on the inclusive production of charged pions, kaons, and nucleons, in proton-proton collisions at c.m. energies from √ s = 23 to 63 GeV at large angles and for the transverse momentum range 0.1 < p T < 4.8 GeV/ c . The dependence of the production spectra on the collision energy √ s , the transverse momentum p T , and the longitudinal rapidity is discussed.
Axis error includes +- 15.0/15.0 contribution (NORMALIZATION ERROR - THE LARGEST SYSTEMATICS).
Axis error includes +- 15.0/15.0 contribution (NORMALIZATION ERROR - THE LARGEST SYSTEMATICS).
Axis error includes +- 15.0/15.0 contribution (NORMALIZATION ERROR - THE LARGEST SYSTEMATICS).
None
THE ERRORS INCLUDE THE UNCERTAINTIES IN THE FIT PARAMETERS SLOPE AND SIG, WHILE THE PURELY STATISTICAL ERRORS ARE ALSO GIVEN.
Cross sections for e+e−→hadrons, e+e−, and μ+μ− near 3684 MeV are presented. The ψ(3684) resonance is established as having the assignment JPC=1−−. The mass is 3684 ± 5 MeV. The partial width for decay to electrons is Γe=2.1±0.3 keV and the total width is Γ=228±56 keV.
No description provided.
We have observed an azimuthal asymmetry in inclusive hadron production by e+e− annihilation at the center-of-mass energy s=7.4 GeV. The asymmetry is caused by the polarization of the circulating beams in the storage ring and allows separate determination of the transverse and longitudinal structure functions. We find that transverse production dominates for x>0.2 where x is the scaling variable 2ps.
No description provided.
No description provided.
No description provided.
The cross section e + e − → π + π − π o has been measured in the φ energy region and at three other energies (915, 990, 1076 MeV) chosen outside the ω and φ resonances. In the same experiment the energy position and the width of the φ resonance have been determined from the φ →K S o K L o channel. It is found that the magnitude and energy dependence of the experimental cross section are well described by coherent production of ω and φ in the whole energy range 770 to 1076 MeV. Our data clearly show an interference effect which corresponds to an opposite sign between the two products g γω g ω →3 π and g γφ g φ →3 π of the coupling constants.
EXPERIMENTAL CROSS SECTIONS - RADIATIVE CORRECTIONS CAN BE SIGNIFICANT.
The radiative decay models of the φ-meson have been studied: e + e − → φ → ηγ →3 γ ; e + e − → φ → π o γ →3 γ . Cross sections σ φ → ηγ →3 γ and σ φ → π o γ →3 γ have been measured at five energies in the φ-meson energy region and clearly show the φ-resonance in the ηγ → 3 γ mode as well as in the π o γ → 3 γ mode. From a Breit-Wigner fit to the experimental data the values of the branching ratios are deduced: B φ → ηγ = (1.5 ± 0.4) × 10 −2 ; B φ → π o γ = (1.4 ± 0.5) × 10 −3 .
REMOVING RADIATIVE CORRECTIONS, THE PHI PEAK CROSS SECTIONS ARE 66 NB +- 25 PCT <ETA GAMMA> AND 6.5 NB +- 30 PCT <PI0 GAMMA>.
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.
The photoproduction of the ψ(3100) meson from a beryllium target has been measured using an 11.8-GeV bremsstrahlung beam. The energy and angular dependence of the measured spectra may be obtained from an elastic nucleon cross section of the form dσdt=(1.01±0.20)exp[(1.25±0.20)t] nb/GeV2. This cross section is exceedingly small in comparison with those of the other vector mesons.
ELECTRON PAIR PRODUCTION FROM BERYLLIUM TARGET. ELASTIC CROSS SECTION VALUE ALLOWS FOR SYSTEMATIC UNCERTAINTIES AND POSSIBLE INELASTIC CONTRIBUTIONS. -TMIN = 0.41 GEV**2.
We have found events of the form e++e−→e±+μ∓+missingenergy, in which no other charged particles or photons are detected. Most of these events are detected at or above a center-of-mass energy of 4 GeV. The missing-energy and missing-momentum spectra require that at least two additional particles be produced in each event. We have no conventional explanation for these events.
X IN RE INCLUDES TWO OR MORE UNDETECTED PARTICLES.
We present the first evidence for K ∗ (1780) production in a non-exchange channel. This comes from a study of the reaction K − p → K° π − p at 14.3 GeV/ c . We also present evidence for K ∗ ° (1780) production in the charge exchange channel K − p → K − π + n. No significant K ππ , K ω and K η decay modes are found. The decay angular distribution, the spin-parity assignments and the production mechanism are discussed. With plausible assumptions on the production mechanism, the J P = 3 − spin-parity is favoured.
No description provided.
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