Total cross sections of K± and p¯ on hydrogen and deuterium were measured in a standard transmission experiment with statistical precisions of the order of 0.05-0.25%. Data were obtained in the momentum range 2.45-3.30 GeV/c for K−N, 1.55-3.30 GeV/c for K+N, and 1.00-3.30 GeV/c for p¯N. Cross sections for the pure isotopic spin states are obtained using a procedure for the deuterium data which takes into account Fermi motion and the shadow effect. Evidence for the following new structures was found: Y1*(2455), Y1*(2620), Y0*(2585), Z1*(2150), Z1*(2500), π1*(2290), π1*(2350), and π0*(2375).
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No description provided.
Total and differential cross sections are presented for the reaction KL 0p→KS 0p from 1.3 to 8.0 GeVc as measured in an exposure of the Stanford Linear Accelerator Center 40-in. hydrogen bubble chamber to a neutral beam. The forward points of dσ(KL 0p→KS 0p)dt together with K+n and K−n total cross sections are used to determine the intercept of the effective Regge trajectory, α(0)=0.47±0.09, and the regeneration phase ϕf=−43∘±8∘.
No description provided.
FULL T REGION.
FULL T REGION.
We present the results on total channel cross-sections obtained in the Saclay 180 l HBC exposed to a separated K− beam at Nimrod. The cross-sections for each channel are given at 13 incident K− momenta between 1.26 and 1.84 GeV/c.
No description provided.
None
STATISTICAL ERRORS ONLY.
With an apparatus slightly improved with respect to a previous one we have studied multihadronic production at the Adone e + e − storage ring up to a maximum center of mass energy of 3 GeV.
No description provided.
No description provided.
No description provided.
The results of an experiment performed at Adone, the 2×1.5-GeV e+e− Frascati storage ring, are presented. During ∼ 1500 hours of running time a total of 5164 electron-positron elastic scattering events (integrated luminosity L=3.5×1035 cm−2) and 605 noncoplanar events from the reaction e+e−→a±+b±+anything (effective integrated luminosity L=2.5×1035 cm−2) have been collected at c.m. energies ranging from 1.4 to 2.4 GeV. Over the energy range explored (1.4-2.4 GeV), corresponding to an average q2 ranging from 0.8 to 2.4 (GeV/c)2, the yield of wide-angle (60°<θ<120°) electron-positron elastic scattering events is found to be in good agreement with the predictions of quantum electrodynamics (QED) (R=σexpσQED=1.05±0.04). The noncoplanar events appear to be of a hadronic nature and are produced with a much higher cross section than predicted on the basis of ρ, ω, φ dominance at these energies. The total cross section for the reaction e+e−→a±b±+anything shows a rapid increase to ∼ 90 nb between 1.0 and 1.5 GeV and falls off slowly to ∼ 50 nb at 2.4 GeV. Cross sections for some of the channels contributing to this multihadron process (e+e−→π+π−π+π−, e+e−→π+π−π+π−+neutrals, e+e−→3π+3π−) have been determined and are reported.
DATA VALUES MEASURED FROM GRAPH IN JOURNAL.
VALUES OF R CALCULATED FROM TOTAL CROSS SECTION.
New data for the reaction π+p→η0Δ++ are presented at 11 momenta between 1.28 and 2.67 GeV/c. Existing data at higher momenta are included in an analysis of the reaction in terms of A2 exchange. An effective trajectory parametrization of the data above 2 GeV/c is shown to describe adequately those data, although it yields an effective trajectory steeper than expected from ρ−A2 exchange degeneracy. An existing Regge-pole model is refitted to the data above 2 GeV/c with generally satisfactory results. Both the effective trajectory parametrization and the Regge model are extrapolated to the lower-momenta data and shown to give remarkably good agreement with the data. Evidence is presented against a dominant contribution to the lower-momenta data from s-channel resonances.
BACKGROUND SUBTRACTED ONLY ABOVE 1.67 GEV/C.
NOT CORRECTED FOR BACKGROUND - MINIMAL DISTORTION EXPECTED. NORMALIZED TO INTEGRATED CROSS SECTION.
ISOTROPIC FIT JACKSON FRAME DENSITY MATRIX ELEMENTS.
An optical spark-chamber counter experiment at Adone, the Italian colliding electron-positron ring, has succeeded in measuring the cross-section for the process e+e−→p\(\bar p\) near threshold (Ec.m.=2.1 GeV). The result isσ(e+e−→p\(\bar p\))=(0.91±0.22) nb.
ISOTROPIC ANGULAR DISTRIBUTION ASSUMED.
None
THIS HADRON PAIR CROSS SECTION PROVIDES ONLY AN UPPER LIMIT TO THE PION FORM FACTOR ABOVE 1.5 GEV SINCE KAON PRODUCTION IS NOT DISTINGUISHED.
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