Approximately 700 events of the reaction K − d → K − π − pp s produced by 5.5 GeV/ c kaons were used to measure the cross section for Kπ elastic scattering in the T = 3 2 state by a Chew-Low extrapolation. The cross section does not exceed 2.1 mb and has no structure for Kπ masses from threshold up to 2.0 GeV.
Chew-Low extrapolation is used for evaluation of the K- P elastic cross section.
The differential cross-section of the reaction γ p→ η p has been measured at the Deutsches Elektronen Synchrotron (DESY) at mean photon energies of 4 and 6 GeV in the momentum transfer range between zero and 1.4 GeV 2 . The data show a slight maximum around t =−0.15 GeV 2 and fall off smoothly till t =−1.4 GeV 2 . There is no indication of a dip around t =−0.5 GeV 2 .
Axis error includes +- 19/19 contribution.
Axis error includes +- 19/19 contribution.
Elastic and inelastic K L S regenerative scattering on copper and lead nuclei have been observed up to a momentum transfer of 0.17 GeV/ c . The elastic differential cross-section is of a ”diffractive” type. It can be described successfully in terms of an optical model only assuming an appreciable neutron excess in the vicinity of the nuclear surface.
No description provided.
No description provided.
We have measured the e + e − → ø reaction by its K + K − decay mode. Using our previous results on K O K O and the 3π decay mode of the ø mesons, we compute Γ ø → e + e − and then compare the whole Orsay results to theoretical predictions.
FITTED CROSS SECTIONS AT PHI PEAK. ONLY PHI --> K+ K- MEASURED HERE - ANALYSIS USES PREVIOUS EXPERIMENTS FOR OTHER CHANNELS: J.E. AUGUSTIN ET AL., PL 28B, 517 (1969).
EXCITATION OF K+ K- CHANNEL MEASURED AROUND PHI RESONANCE AT 13 ENERGIES.
The differential cross sections for the γ + n → π O + n reaction have been measured at the photon energies of 500–900 MeV. The ratios, R oo = [ d δ d Ω(γ n → π o n ) ] [ d δ d Ω(γ p → π o p ) ] , have been obtained at the c.m. pion angles of 60 O , 90 O , 105 O , 120 O , and 140 O .
Axis error includes +- 0.0/0.0 contribution (8 TO 11////).
Axis error includes +- 0.0/0.0 contribution (8 TO 11////).
Axis error includes +- 0.0/0.0 contribution (8 TO 11////).
We present results of measurements on photoproduction of ρ mesons. Analysis of 106 measured ρ events in a four-dimensional data matrix dσ(A, m, p, t⊥)dΩdm with dimensions 14×20×10×20 yields precise information on nuclear density distributions for ρ production. We obtain for the Woods-Saxon radii R(A)=(1.12±0.02)A13 and, using the vector dominance model, σρN=26.7±2.0 mb and γρ24π=0.57±0.10.
No description provided.
Polarization of Λ hyperons and differential cross sections for the reaction γ+p→K++Λ were measured at the K+-meson center-of-mass angles around 45°, 70°, and 90° for the incident photon energies of 1054, 1100, and 1160 MeV. The K+ mesons were detected with a magnetic spectrometer and a velocity-selection system based on the energy loss and the time of flight. The polarization of Λ was determined by measuring the up-down asymmetry of protons in the decay Λ→pπ− with respect to the production plane. The results show a dominant sinθK* dependence of the polarization at the region of the third resonance and are consistent with a contribution of the P11 resonance with a mass of about 1700 MeV.
No description provided.
No description provided.
No description provided.
Neutron-proton total cross-sections were measured in the momentum range from 8 GeV/ c to 21 GeV/ c with an accuracy of better than 2% using a 0 o neutron beam at the CERN Proton Synchrotron. The np total cross-section drops from 39.7 mb at 8 GeV/ c at 21 GeV/ c , and thus follows closely the pp total cross-sections in this momentum interval.
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.
High energy v -nucleus cross sections have been compared for Pb, Fe, Al and C as target nuclei, exposed to the CERN v -beam. The events with θ vμ < 29 0 and p μ ⪆ 1 GeV /c have rates in the ratio of the mass number of the nuclei. Also a restricted sample with q 2 ⪅ 0.1 (GeV/ c ) 2 and θ vμ < 5 0 does not reveal a theoretically predicted deviation from A -proportionality, although due to the limited statistical accuracy in this restricted sample an “ A 2 3 - contribution ” of several tenths cannot be excluded either.
Only statistical error is presented.
Only statistical error is presented.
Only statistical error is presented.
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