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.
The π − p→n γ and π − p→n π ° differential cross sections have been measured for −0.9< cos θ ∗ <−0.45 (θ ∗ c.m. scattering angle) at 475 MeV/ c and 550 MeV/ c incident momenta. The π − p→n γ measurement is a good check of the detailed balance principle in the electromagnetic interactions of hadrons at these energies and is in good agreement with Walker's analysis. On the other hand the π − p→ π °n extrapolated values of 180° allows one to verify that the phases of the A 1 2 and A 3 2 amplitudes are equal.
No description provided.
No description provided.
BACKWARD CROSS SECTION ESTIMATED BY LEGENDRE POLYNOMIAL FIT.
The differential cross sections for the reaction γ + n → π 0 + n have been measured at pions angles of 45°, 60°, 105°, 120° and 140° in the c.m.s. for photon energies of 500–900 MeV. Both π 0 meson and recoil neutron from a liquid deuterium target were detected with a pair of Čerenkov counters combined with lead spark chambers and a hodoscope consisting of 16 modules of plastic scintillation counters.
The target asymmetry T = ( σ ↑ − σ ↓)/( σ ↑ + σ ↓) for the reaction γ p → π + n has been measured at the Bonn 2.5 GeV electron synchrotron for a pion c.m. angle of 40° and γ energies between 0.5 and 2.2 GeV. Butanol was used as the target material. About 35% of the protons could be polarized using the dynamic-polarization method in a continuous-flow cryostat operating at 1°K and 25 kG. The π + mesons were detected in a magnetic-spectrometer system. Considerable structure in the asymmetry was observed.
Axis error includes +- 11/11 contribution.
The differential cross section has been measured for the reaction γ +p→p+ π o at the Bonn 2.5 GeV electron synchrotron in the energy range from 0.4 to 2.2 GeV for a c.m. angle of 150 degrees. The protons were detected in a magnetic spectrometer system. The excitation curve shows a distinct resonance structure. The total corrections to the counting rate are about 3%. The contribution of the process γ +p→p+2 π was separated. The uncertainty of this separation leads to an error of about 4% in the cross section.
No description provided.
No description provided.
We present complete results concerning the five reactions K − p → Λω , K − p → Λφ , K − p → Σ 0 ϱ and K − p → Σ 0 φ . The experimental data are well described by exchange mechanisms and the agreement with the SU(3) symmetry predictions is excellent.
FORWARD AND BACKWARD CROSS SECTIONS ARE FOR COS(THETA) > AND < 0. SLOPE DETERMINED FOR -TP = 0.2 TO 1.0.
AUTHORS ALSO GIVE CORRELATIONS OF LAMBDA POLARIZATION WITH THE MESON POLARIZATION.
No description provided.
Substantial production of the resonances ϱ, f and ω has been observed in this reaction. In contrast with the channel p p → 2π + 2π − , associated production of resonances was found to occur. The behaviour of the associated production of ω-mesons with other resonances is shown to be consistent with some very simple assumptions. Alternative methods of displaying data for p p → ππω are discussed; it is shown that the longitudinal phase plot for this reaction is unlike that obtained for any previously reported reaction. Reasonable agreement for the behaviour of this channel is found with the multiperipheral model of Chan, Łoskiewicz and Allison.
STATISTICAL ERRORS ONLY. FOR MULTIPLE PI0 PRODUCTION, RESULTS ARE MODEL DEPENDENT.
ANALYSIS OF 5PION FINAL STATE. DISTRIBUTION FITTED WITH FIXED MASS AND WIDTH RESONANCES, THEN ONLY EVENTS ABOVE (FITTED) BACKGROUND TAKEN. CROSS SECTIONS CALCULATED BY PDG (COMPILATION PDG3).
New measurements on the reactionsγp→K + Λ and γp→K + Σ o have been performed at the DESY synchrotron at c.m. angles around 90° and photon lab. energies from 1.19 to 1.68 GeV. The produced K + mesons were analyzed by a magnet spectrometer, two thresholdCˇerenkov counters and a time-of-flight measurement. The obtained differential cross-section data show a smooth energy behaviour for the K + Λ production whereas for theK + Σ o production the data trace out a bump at a c.m. energy W ≈ 1.9GeV.
No description provided.
No description provided.
Differential cross section for π + photoproduction on hydrogen have been measured over a photon energy range from 220 to 425 MeV and for pion c.m. angles between 15° and 70°. The pions have been analysed in angle and momentum by a magnetic spectrometer.
No description provided.
No description provided.
No description provided.
Differential cross sections for neutral-pion photoproduction on hydrogen in the region of the first resonance have been measured by two independent experiments detecting the recoil protons. The results of both measurements have been combined into one set of cross sections covering the photon energy range from 200 to 440 MeV at pion c.m. angles between 50 and 160 degrees.
No description provided.
No description provided.
No description provided.
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