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.
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.
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.
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).
A search for narrow resonances in the reaction e + e − → hadrons in the mass regions 1915–2345 MeV and 2970–3090 MeV has been perforned at ADONE, the Frascati storage ring. With 90% confidence level our data exclude the production of narrow resonances with integrated cross section larger than 20% of the integrated cross section for production of the J/Ψ (3100 MeV).
No description provided.
We have searched for possible narrow resonances produced in e + e − annihilation at Adone, in the mass regions 1910–2545 MeV and 2970–3090 MeV. No evidence has been found for narrow resonances, within the sensitivity of the present work: we deduce an upper limit on the energy integrated resonant cross section of about 10% of the J/ψ(3100) corresponding value.
No description provided.
The reactions e + e − → hadrons and e + e + e − →e + e − have been studied at the J/gY (3100) resonance). The relative weights of the topological cross sections for fixed charged multiplicity are σ 2 =(32±5)%, σ 4 =(49±8)%, σ 6 =(18±3)%, and σ 8 =(1±0.6)%. The average pion multiplicities are 〈 n ch 〉=3.8±0.3 and 〈n π o 〉=3.1±0.8 . The decay widths are Γ e =(4.6±0.8) keV, Γ h =(59±24) keV, and Γ =(68±26) keV.
CROSS SECTION AROUND RESONANCE.
CROSS SECTION JUST BELOW J/PSI.
MULTIPLICITY AT J/PSI.
Results on the inclusive reactions K − p → K ∗− (890) + X + and K − p → K ∗0 (890) + X 0 at 14.3 GeV/c are presented. A comparison is made with previous data and with the reaction K − p → K 0 + X at 14.3 GeV /c . Predictions of a triple-Regge model for the variation of the unnatural and natural parity exchanges with the mass of the X system are examined. The experimental values of the structure functions are compared with those calculated from a quark model.
No description provided.
No description provided.
No description provided.
We present a study of the transverse momentum spectrum of π 0 's produced at c.m. angles θ = 90° and 53° in pp collisions at √ s = 23.6, 30.8, 45.1, 53.2, and 62.9 GeV. The experiment was performed with a lead-glass detector. The data can be described with the usual parametrization p T −n ƒ;(x T , θ) , with n = 7.2 ± 0.2. Comparison between the 90° and 53° data further indicates no appreciable dependence on θ , at least for x T < 0.3. Two-particle inclusive cross sections for π 0 's produced alongside are also presented. They are observed to have a dependence upon the transverse momentum of the dipion similar to that of single-particle cross sections and with the same value of n . Two-photon decays of η mesons are observed between 3 and 4 GeV/ c transverse momentum with a production cross section half of that of π 0 .
No description provided.
No description provided.
No description provided.
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