The polarized target asymmetry in the reaction γp→π°p has been measured at c.m. angles around 100° for photon energies between 0.4 and 1.0 GeV by detecting both the recoil proton and the π°. The result is compared with recent analyses.
No description provided.
The polarized target asymmetry for γ + p → π + + n was measured at c.m. angles around 130° for the energy range between 0.3 and 1.0 GeV. A magnetic spectrometer system was used to detect π + mesons from the polarized butanol target. The data show two prominent positive peaks at 0.4 and 0.8 GeV and a deep minimum at 0.6 GeV. These features are well reproduced by the phenomenological analysis made by us.
No description provided.
The polarized target asymmetry in the reaction γ p → π 0 p has been measured at c.m. angles of 30°, 80°, 105° and 120° for incident photon energies below 1 GeV. Two decay photons from π 0 were detected in coincidence at 30°, and at the other angles recoil protons and single photons from π 0 were detected. The results are compared with recent phenomenological analyses.
No description provided.
The polarized target asymmetry for the process γ p → π + n has been measured for incident photon energies below 1.02 GeV over a range of c.m. angles from 40° to 160°. π + mesons from a polarized butanol target were detected by a magnetic spectrometer. The results are compared with predictions given by existing analyses. A tentative interpretation of the data is performed, and a larger contribution of S-wave resonances is suggested. The photocouplings of dominant resonances were hardly changed by the inclusion of new data and they seem to be almost uniquely determined.
No description provided.
We have measured the differential cross section for π − p elastic scattering at eight incident momenta, 2.06, 2.26, 2.45, 2.65, 2.86, 3.05, 3.26 and 3.48 GeV/ c , in a wide range of c.m. scattering angle between 15° and 160°. A pronounced dip-bump structure has been found at large angles. Details of the structure are quantitatively described as functions of the incident momentum.
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We have studied the photoproduction of Jψ mesons on H, Be, Fe, and Pb targets using real photons at a mean energy of 120 GeV. The pT2 spectra were used to separate the coherent diffractive signals from the incoherent signals. Parametrizing the per-nucleus cross sections in terms of power-law dependences, Aα, we find that αcoh=1.40±0.06±0.04 for the coherent diffractive signals and αincoh=0.94±0.02±0.03 for the incoherent signals.
CROSS-SECTIONS ARE RELATIVE TO THAT FOR INCOHERENT J/PSI PRODUCTION OFF BERYLLIUM.
Clear evidence is presented for the production of an Ω ∗− resonance of mass 2253±13 MeV/ c 2 and width 81±38 MeV/ c 2 in K − p interactions at 11 GeV/ c . The state is observed in the Ξ (1530)K̄ decay mode, and the corresponding inclusive cross section is estimated to be 630±180 nb. Comparisons are made with theoretical predictions and with similar states observed inhyperon beam induced data.
No description provided.
High statistics data for the reaction K − p→K − π + n at 11 GeV / c have been obtained in the LASS spectrometer at SLAC. A spherical harmonic moments analysis provides clear evidence for the production of the complete leading orbitally excited K ∗ series up through J P = 5 − . New measurements are made of the masses and widths of the 1 − K ∗ (892), 2 + K ∗ (1430 ), 3 − K ∗ (1780), and 4 + K ∗ (2060), and evidence is presented for the production of a new K ∗ state at 2382 MeV / c 2 with spin-parity 5 − .
Unnormalised acceptance corrected spherical moments.
Correlation matrices.
Correlation matrices.
The K − η effective mass spectrum in the reaction K − p→K − π + π − π 0 p at 11 GeV/ c has a prominent peak at ≈1.75 GeV/ c 2 , which is shown to be due to the K 3 ∗ (1780) by a spherical harmonic moments analysis and amplitude decomposition; there is no significant signal for K 2 ∗ (1430). The measured branching fractions for the leading L =1 and L =2 K ∗, s, [BF(K 2 ∗ (1430)→Kη) <0.45% at the 95% CL and BF ( K 3 ∗ (1780)→ Kη )=9.4±3.4%] confirm the SU(3) prediction that the Kη channel couples preferentially to odd spin K *, s.
Numerical data of acceptance corrected spherical harmonic moments requested from authors.
Including systematic error.
We have found 122 charmed-particle decays among 3855 neutrino interactions located in the fiducial volume of a hybrid emulsion spectrometer installed in the Fermilab wide-band neutrino beam. We obtain an average relative charmed-particle production cross section of σ(ν μ → c μ − ) σ(ν μ →μ − ) =4.9 −0.6 +0.7 % , at an average neutrino energy of 22 GeV. We also obtain a production rate of σ(ν μ → c c ν μ ) σ(ν μ →ν μ ) =0.13 −0.11 +0.31 % , if we assume that there was an undetected muon, a limit of σ(ν μ → c c μ − ) σ(ν μ → c μ − )<3% (90% CL ) can be obtained. Other cross section ratios and limits are also presented.
No description provided.
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