New data on differential cross sections and polarisation are presented at nine incident momenta up to 1334 MeV/ c . An energy-dependent phase-shift analysis has been made and resonance parameters are given.
No description provided.
No description provided.
No description provided.
We have measured π±p and pp elastic differential cross sections in the range |cosθc.m.|<0.35 for incident momenta from 2 to 9.7 GeV/c for π−p and pp and from 2 to 6.3 GeV/c for π+p. We find that the fixed-c.m.-angle πp differential cross sections cannot be described as simple functions of s. The data are compared to the energy and angular dependence predicted by the constituent model of Gunion, Brodsky, and Blankenbecler.
No description provided.
No description provided.
No description provided.
Large-angle π±p elastic-scattering cross sections, measured between 2 and 9 GeV/c in fine intervals of incident momentum and scattering angle, are used to search for cross-section fluctuations occurring for small changes in the center-of-mass energy as suggested by Ericson and Mayer-Kuckuck and by Frautschi. Significant fluctuations are observed.
No description provided.
No description provided.
No description provided.
The cross section for elastic scattering of 794-MeV neutrons by deuterium has been measured for neutron center of mass angles from 139° to 179°. The angular distribution is fitted very well both by an empirical function αeβ(μ−μ180∘) and by a calculation that uses the one parameter Craigie-Wilkin triangle diagram technique. [NUCLEAR REACTION nH2→H2n, E=794 MeV; measured σ(θ). Calculated σ(θ) with triangle diagram techniques.]
X ERROR H = 12.60 CM. X ERROR D(THETA) = 2.0000 DEG.
The invariant mass spectrum of neutral final states produced in π − p charge-exchange scattering at 40 GeV/ c has been studied, searching for heavy particles decaying in 2γ. A peak is observed around 2.85 GeV/ c 2 . The cross section of the reaction π − p→X(2.85)+n, times the branching ratio of the X→2 γ decay, is measured to be σ × BR ⋍ 2 × 10 −34 cm 2 .
MEAN VALUE OF -T = 0.28 +- 0.04 GEV**2.
None
No description provided.
New results on a high statistics measurement of pion-nucleon charge exchange scattering at 40 GeV/ c , extending in momentum transfer up to − t = 1.8 (GeV/ c ) 2 , are reported and compared with an optical impact parameter model, together with previous data for the reaction π − p → ηn at the same energy. The imaginary part of the pole trajectory b 0 ( s ) is determined from the slope of the tangent to the maxima of (−t) 1 2 d σ d t . The linear increase of Im b 0 ( s ) with log s , which has been observed at low energies, continues up to 40 GeV/ c .
.
AT SMALL -T, THE BINNING TENDS TO SMEAR OUT THE FORWARD DIP.
A study of the inclusive and semi-inclusive Λ and Λ production in K + p interactions at 32 GeV/ c is presented. The inclusive cross sections for Λ and Λ amount to 0.78 ± 0.05 and 0.42 ± 0.04 mb thus showing a remarkable growth between 16 and 32 GeV/ c with a factor of 1.7 for Λ and 2.8 for Λ . Target and beam fragmentation processes are found to be dominant for Λ and Λ production respectively with the following lower limits for the corresponding cross sections: σ(p → K + ʌ) > 0.5 mb and σ(K + → p ʌ ) > 0.3 mb . Although the early scaling conditions are fulfilled for the Λ production in the target fragmentation region, and Λ production in the beam fragmentation region, scaling is not observed between 16 and 32 GeV/ c in the x and p T 2 Feynman variables. The Λ production is found to be very similar in the K + p inclusive reaction at 32 GeV/ c and in the semi-inclusive reaction K − p → Λ K K X at the same energy. The Λ Λ pair production cross section increases significantly in K + p interactions from 16 to 32 GeV/ c where it reaches the value σ Λ Λ = 47 ± 11 μ b . The cross sections for Λ or Λ produced in association with an identified proton are also given and discussed.
No description provided.
No description provided.
Measurements were made of the differential cross sections for the charge exchange of K − mesons on protons at momenta of 25 and 40 GeV/ c using a high-precision spectrometer with no magnetic field. In the range 5–40 GeV/ c the reaction cross section follows a power-law dependence p K − −1.52 . In the snall momentum transfer region (− t ⪅ m π 2 ) a minimum is observed, similar to that discovered at lower energies. The differential cross sections t = 0 are considerably less than those predicted by the Regge-pole model. The parameters of the effective trajectory are determined.
.
.
None
No description provided.
No description provided.
No description provided.
Forum