Data are presented on the polarization parameter in pp and pn elastic scattering at 11.8 GeV/c for four-momentum transfers −t=0.15 to 0.9 GeV2. In contrast to lower energies where the pn polarization is positive, it is slightly negative at 11.8 GeV/c; averaging the data from −t=0.18 to 0.5 GeV2 we find P(pn)=(−0.9±0.5)%, to be compared with P(pp)=(5.6±0.8)%. These data, combined with our previous data at lower energies, show that the I=0 single-flip exchange amplitude has an anomalously rapid energy dependence.
No description provided.
We observe a K−π+ state at 1786 ± 8 MeV with a width 95 ± 31 MeV in the reaction K−p→K−π+n at 6 GeV/c, from an experiment carried out at the Brookhaven National Laboratory multiparticle spectrometer.
ERROR INCLUDES SYSTEMATIC NORMALIZATION UNCERTAINTY.
We report results from a measurement of the inclusive processes pp→Xp and pd→Xd in the range 5<Mx2s<0.1, 0.01≲|t|≲0.1 (GeV/c)2, and incident proton momenta of 65, 154, and 372 GeV/c. Both pp and pd data show an exponential t dependence and a dominant 1Mx2 behavior for Mx2s≲0.05. By comparing pp and pd data we test factorization and, using the Glauber model, we measure the XN total cross section, σXN=43±10 mb.
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We have measured the polarization parameter in π − p→K + Σ − backward scattering at 3.5 GeV/ c incident momentum, in the u -range −0.6< u <0.1 GeV 2 . The apparatus consisted of a polarized target in a spectrometer magnet, counter hodoscopes for time-of-flight measurements, a large water Čerenkov counter for kaon tagging, and wire spark chambers. After identification of the kaons, the reaction was selected by a missing-mass technique. An isospin analysis has been carried out to separate the contributions of the various isospin exchange amplitudes in the u -channel.
No description provided.
A two-arm spectrometer for simple event topologies is described. Its main characteristics are: (i) large solid-angle acceptance for the forward emitted particles, owing to the absence of magnetic-momentum analysis; (ii) high-resolution time-of-flight measurement of the recoil proton, in the momentum-transfer range 0.05 < | t | < 1 (GeV/ c ) 2 ; (iii) high data-taking rate and on-line pattern recognition.
No description provided.
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K*(892)+ REGION.
High statistics data for the reactions K ± p → K S 0 π ± p at 10 GeV/ c are analysed. The K ∗ (1 − ), K ∗ (2 + ), and K ∗ (3 − ) resonance parameters and production cross sections are calculated. The Kπ production amplitudes are determined as a function of t and the produced Kπ mass. Isoscalar natural-parity-exchange (NPE) is dominant. The t dependence of the K ± NPE amplitudes have a cross-over at t = −0.3 (GeV/ c ) 2 for both K ∗ (890) and K ∗ (1420) production, being more pronounced for the K ∗ (1420). Natural-parity-exchange interference effects are isolated. The NPE amplitudes are decomposed into pomeron-, f-, and ω-exchange contributions. S-wave Kπ production is found to be consistent with the Kπ partial-wave analyses of charge-exchange reactions.
CORRECTED FOR BACKGROUND, BREIT-WIGNER TAILS AND T-ACCEPTANCE. SYSTEMATIC ERROR INCLUDED.
DATA FOR K PI PRODUCTION AND ANGULAR DISTRIBUTIONS ARE IN THE PRECEDING PAPER, R. BALDI ET AL., NP B134, 365 (1978).
We report measurements at the CERN PS of the production cross section of J/ψ(3.1) by 24 GeV protons on hydrogen, carbon, and tungsten.
No description provided.
ASSUME B.R.(E+E-) =0.069.
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We have measured the single-particle inclusive cross sections for p+p→π±+X, K±+X, p+X, p¯+X in the low-p⊥ region (≲ 1.5 GeV/c) as a function of the radial scaling variable XR in p−p collisions at 100, 200, and 400 GeV at Fermilab. The measured π+π− and K+K− ratios are shown to be remarkably similar to the same ratios which have recently been measured at large p⊥ at 90° in the center-of-mass system.
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A clear, prompt dimuon signal has been observed in a low-statistics streamer-chamber experiment with 16-GeV/c πp interactions. The good mass resolution makes it possible to identify the contributions from ρ and ω decays and η and ω Dalitz decays. An excess of events is observed in the mass region ∼400-600 MeV which is not accounted for by the above-mentioned decays.
The data with PI+- beam obtained from the combination of PI+ and PI- beams.
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