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 results of measurements of K ± p and p p elastic scattering and of the annihilation reactions p p →π + π − and p p → K + K − at an incident laboratory momentum of 5 GeV/ c . Nearly complete angular distributions were obtained. Results are also presented for π -meson proton elastic scattering in the momentum transfer ranges 2 < − t < 8 (GeV/ c ) 2 (for π + ) and 0.16 < − t < 7 (GeV/ c ) 2 (for π − ). All measurements were done in one experimental geometry. The measured differential cross sections range from 10 to 10 −5 mb/(GeV/ c ) 2 .
-U = T + 8.486 GEV**2.
THE DATA FOR -T = 7.31 TO 8.45 GEV**2 WERE NORMALIZED TO OTHER EXPERIMENTS.
-U = T + 8.304 GEV**2.
Topological and channel cross sections are given for the more common final states produced in K − p interactions at 8.25 GeV/ c together with the single particle inclusive cross sections. We present cross sections for prominent resonances occurring in final states K N (nπ) and find the resonance fractions to be roughly independent of multiplicity.
SE FOLDED.
No description provided.
No description provided.
We have measured the reaction γ p → p π + π − in the DESY 1 m Streamer Chamber. The dominant ϱ o production is analyzed in terms of various models.
No description provided.
FOR ALL EVENTS.
FOR ALL TWO PION EVENTS.
The asymmetry A = (σ + −σ − ) (σ + +σ − ) of the reaction γ p↑↓ → π 0 p was measured at the Deutsches Elektronen Synchrotron DESY, Hamburg at a mean photon energy of 4.0 GeV in the four-momentum transfer range 0.2 (GeV/ c ) 2 ⩽ −t ⩽ 1.1 (GeV/ c ) 2 in steps of approximately 0.08 (GeV/ c ) 2 . The π 0 -meson and the proton were detected in coincidence. The asymmetry is compatible with zero in the t -range 0.2 (GeV/ c ) 2 ⩽ − t ⩽ 0.4 (GeV/ c ) 2 and negative in the t -range ⩾ 0.5 (GeV/ c ) 2 .
No description provided.
The study of 620 hadron pairs produced in the s -range (1.44−9.0) GeV 2 , has yielded 110 collinear hadronic events. Their identification in terms of π and K mesons allows the determination of the time-like electromagnetic from factors of these pseudoscalar mesons in the above time-like range. The total number of (e + e − ) events observed in the same experimental conditions is 18 048.
No description provided.
No description provided.
The p p → n n polarization has been measured at 8 GeV/ c and for − t values ranging from 0 up to 0.8 (GeV/ c ) 2 . A small and negative polarization has been found.
ERRORS INCLUDE STATISTICAL AS WELL AS RELATIVELY SMALL SYSTEMATIC EFFECTS.
The observation of 21 K + K − pairs in 38 hadron pair events produced at 1.5, 1.6, and 1.7 GeV total centre-of-mass energies in e + e − annihilations, establishes that time-like photons produce K pairs and π pairs with comparable rates in this energy range. The K-meson electromagnetic form factor at a mean s -value of 2.4 GeV 2 is measured to be | F K | = 0.50±0.08. The number of e + e − pairs observed in the same angular and energy range is 5148.
No description provided.
In a counter and wire spark chamber experiment with a polarized target, backward kaons were detected, and the Σ + 's identified by a missing-mass technique. An average polarization of −0.08 ± 0.05 was found for −0.2 < u < 0.1 GeV 2 .
THE MEAN POLARIZATION FOR ALL EVENTS IS -0.08 +- 0.05.
The inclusive production al all charged particles of transverse momentum p T between 1.5 and 4.4 GeV/ c at centre of mass angles 90° and 59.4° from p-p-collisions with √ s = 44 and 53 GeV has been measured. No strong energy dependence is observed for these transverse momenta.
Errors are statistical only.
Errors are statistical only.
Errors are statistical only.
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