We have searched the mass region 3.2 to 5.9 GeV for evidence of narrow resonances in e+e−→hadrons. We find no evidence for any such resonances other than the ψ(3695) in this region with a sensitivity ranging from about 12 to 45% of the integrated cross section of the ψ(3695). The more stringent bounds apply to resonances of a few MeV width, while the looser bounds apply to resonances of up to 20 MeV width.
EXTREAMLY GOOD DATA, MUST BE ASCED FROM AUTHORS.
The total cross section for hadron production by e+e− annihilation has been measured at center-of-mass energies between 2.4 and 5.0 GeV. Aside from the very narrow resonances ψ(3105) and ψ(3695), the cross section varies between 32 and 17 nb over this region with structure in the vicinity of 4.1 GeV.
No description provided.
MEAN CHARGED MULTIPLICITY. ERRORS ARE STATISTICAL ONLY.
From a 150 000-photograph exposure, we analyzed the p¯d→p¯psn reaction, ps denoting a proton stopping in the deuterium-filled bubble chamber. Choosing kinematical regions in which the ps can be recognized as a spectator, we studied the p¯n→p¯n process. From the observed p¯n diffraction peak, we obtained an exponential slope for the four-momentum-transfer distribution of bn=9.4±0.8 (GeV/c)−2, the elastic p¯n cross section being estimated as σe(p¯n)=16.5±2.4 mb. The present values in conjunction with those obtained at ≈1.8 and 3.5 GeV/c show that in this region bn and σe(p¯n) decrease with increasing incident momentum. We compared our data with the reactions np→np at ≈5.4 GeV/c and p¯p→p¯p at 5.7 GeV/c. The p¯n→p¯n and np→np differential cross sections exhibit a crossover phenomenon while p¯p and p¯n elastic scattering show an isospin dependence. We also analyzed the p¯d→p¯psn reaction by means of the Glauber formalism.
No description provided.
No description provided.
The inclusive ϱ ° production cross section has been measured in the reaction π − p → π + π − X at 205 GeV/ c . We find σ ( ϱ ° ) = 13.5 ± 3.4 mb, with most of the production occuring in the central region. Assuming σ ( ϱ + ) ≈ σ ( ϱ − ) ≈ σ ( ϱ ° ), it is concluded that approximately one-third of the pions at this energy come from ϱ -decay.
No description provided.
No description provided.
No description provided.
The experimental upper limit for the diffractive photoproduction of the ψ(3105) is 29 nb, with 90% confidence, at an average photon energy of 18.2 GeV.
No description provided.
We report on the results at ADONE to study the properties of the newly found 3.1-BeV particle.
No description provided.
We have observed a very sharp peak in the cross section for e+e−→hadrons, e+e−, and possibly μ+μ− at a center-of-mass energy of 3.105±0.003 GeV. The upper limit to the full width at half-maximum is 1.3 MeV.
No description provided.
None
ONE EVENT SEEN - PROBABLY AN ANTIPROTON.
In a 35 000-picture exposure of the 30-in. hydrogen bubble chamber to a 300-GeV/c proton beam at the Fermi National Accelerator Laboratory, 10054 interactions have been observed. The measured total cross section is $40.68 \pm 0.55$ mb, the elastic cross section is $7.89 \pm 0.52$ mb, and the average charged-particle multiplicity for inelastic events is $8.S0 \pm 0.12$.
QUOTED ERRORS INCLUDE EFFECTS OF CORRECTIONS.
No description provided.
In a 48 000-picture exposure of the Fermilab 30-inch hydrogen bubble chamber to a 205 GeV/ c π − beam, we have measured 169 events of the reaction, π − p → π − π + π − p, with a cross section of 635 ± 61 μ b. This reaction proceeds almost entirely via low mass π − → 3 π and p → p ππ dissociation. Factorization is satisfied for p → pππ dissociation in πp and pp interactions.
No description provided.
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