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No description provided.
No description provided.
We have measured small angle elastic pion-proton scattering in 40 and 50 GeV c π − beams at Serpukhov. Analysis of the data in the Coulomb interference region yields a value for the ratio of the real to the imaginary part of the strong amplitude, ϱ (0)=−0.074 ± 0.033 at 40 GeV/ c and ϱ (0)=−0.006 ±0.026 at 50 GeV/ c
STATISTICAL ERRORS ONLY.
STATISTICAL ERRORS ONLY.
The final states\(\bar p\)pω and\(\Delta ^{ ++ } \bar \Delta ^{ -- } \pi ^0 \), produced in the reaction\(\bar p\)p →\(\bar p\)pπ+π−π0 (6435 events) at 5.7 GeV/c, are studied. Cross-sections are presented, and general features of the resonances produced are investigated. Spin alignment of the ω’s, reported earlier, is studied. An enhancement is observed in the ωp (ω\(\bar p\)) mass plot of mass (1810±15) MeV and width (87 ± 20) MeV.
No description provided.
Total cross sections of π± and K± on protons and deuterons have been measured at 50, 100, 150, and 200 GeV/c. All of the cross sections rise with increasing momentum.
No description provided.
PARTICLE-ANTIPARTICLE CROSS SECTION DIFFERENCES - SOME COMMON ERRORS CANCEL.
We have measured deep inelastic muon-deuteron scattering in the range 0.4<Q2<3.4 and 1.6<ν<5.6 GeV. We have extracted the neutron structure function and find that νW2n differs significantly from νW2p, as also found in e−d scattering. To compare μ−d and e−d scattering we form the ratio r(Q2)=(νW2)μd(νW2)ed=N(1+Q2Λ2)−2 and find N=0.925±0.038 and 1Λ2=−0.019±0.016.
No description provided.
Proton and antiproton total cross sections on protons and deuterons have been measured at 50, 100, 150, and 200 GeV/c. The proton cross sections rise with increasing momentum. Antiproton cross sections fall with increasing momentum, but the rate of fall decreases between 50 and 150 GeV/c, and from 150 to 200 GeV/c there is little change in cross section.
No description provided.
ANTIPARTICLE-PARTICLE CROSS SECTION DIFFERENCES.
We report measurements of the ratio of the deep-inelastic electron-neutron to electron-proton differential cross sections in the threshold ( ω <3) region. The ratio was found to scale and to decrease monotically with decreasing ω . No violation of the quark model lower bound of 0.25 was observed in the ratio.
DATA ARE AVERAGED THROUG AVAILABLE KINEMATIC REGION.
In a study of the missing-mass spectrum near 1 GeV in the reaction π−+p→MM+n at three incident momenta near 2 GeV, we find no evidence for the recently reported narrow neutral mesons at 940, 963, and 1033 MeV.
No description provided.
Total cross sections of p¯p and p¯d have been measured between 360 and 1050 MeV/c, with high statistical precision. Structures are observed in both cross sections at about the same momenta. For p¯p, the central mass is 1932±2 MeV/c2, and a fit to the data with a simple Breit-Wigner resonance plus background gives Γ=9−3+4 MeV/c2. The data suggest that the structures are in the isospin-1 state.
No description provided.
Measurements of π±p, K±p, pp, and p¯p elastic scattering are presented for incident momenta of 3, 3.65, 5, and 6 GeVc and momentum transfers typically 0.03 to 1.8 GeV2. The angle and momentum of the scattered particle were measured with the Argonne Effective Mass Spectrometer for 300 000 events, yielding 930 cross-section values with an uncertainty in absolute normalization of ±4%. Only the K+ and proton data show any significant change in slope of the forward diffraction peak with incident momentum. The particle-antiparticle crossover positions are consistent with no energy dependence, average values being 0.14 ± 0.03, 0.190 ± 0.006, and 0.162 ± 0.004 GeV2 for π' s, K' s, and protons, respectively; these errors reflect both statistics and the ±1.5% uncertainty in particle-antiparticle relative normalization. Differences between particle and antiparticle cross sections isolate interference terms between amplitudes of opposite C parity in the t channel; these differences indicate that the imaginary part of the odd-C nonflip-helicity amplitude has a J0(r(−t)12) structure for −t<0.8 GeV2, as predicted by strong absorption models. The cross-section differences for K± and proton-antiproton are in qualitative agreement with the predictions of ω universality, the agreement improving with increasing energy. The corresponding quark-model predictions relating the π± and K± differences failed by more than a factor of 2. We have combined our π± cross sections with other data to better determine the πN amplitudes in a model-independent way; results of this analysis are presented.
No description provided.
No description provided.
No description provided.
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