We measured the elastic and inelastic scattering of electrons on deuterium at 180° for four incident energies (70, 140, 210 and 280 MeV). The data were analysed with a technique allowing an accurate comparison between experiment and theory. We observed a good agreement for the inelastic data with the expected cross section, using the presently available models and nucleon form factors. The experimental elastic cross section is systematically larger than the predicted cross sections.
No description provided.
No description provided.
No description provided.
We have studied the proper time distribution of coherent π + π − decays from a 3 – 10 GeV/ c K L o beam incident on a one meter liquid hydrogen target using a wire spark chamber spectrometer in the 3 0 neutral beam at SLAC. We find ∣(ƒ(0) − ƒ (0))/k∣ = 0.43 ± 0.11 mb , φ(ƒ(0) − ƒ (0)) = -101 0 ± 42 0 .
No description provided.
Coherent photoproduction of ϱ 0 and ω at E γ = 4.3 GeV is observed. The ratios ϱ 0 d/ ω d and ϱ 0 d/ ϱ 0 p are discussed and compared with theoretical predictions. By comparing our data with total photoabsorption cross sections we determine the direct vector meson-photon coupling to be γ ϱ 2 /4 π = 0.29 ± 0.06. With this value we find the VDM relations between photoproduction and Compton scattering well satisfied.
'1'.
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No description provided.
Data from the reactions π−p→π−π−π+p and π+p→π+π+π−p have been obtained at 16 GeV/c in approximately equal samples from the BNL 80-in. hydrogen bubble chamber. We have studied both reactions for resonance production and compared our results with predictions of the one-pion-exchange model (OPEM) calculated by Wolf. The four-body longitudinal phase-space (LPS) plot suggested by Van Hove was used to analyze the data from both reactions. The events were separated according to distinct regions of the LPS plot in order to study the following classes of quasi-two-body final states: (1) diffractively produced three-pion states, (2) diffractively produced ππp states, (3) double-resonance production such as ρ0Δ++, (4) single-resonance production such as π−π−Δ++. The Van Hove analysis provided a much cleaner separation of resonances from background effects than the usual techniques. We observe production of the A1 and A2 mesons as well as the N*(1470) and N*(1700) isobars in the π+π−p system for both reactions. There is strong formation of the doubly resonant states ρ0Δ++ and f0Δ++ and the general features of the nondiffractive events are all in good agreement with one-pion exchange. Detailed comparisons between the data and the OPEM in each LPS plot region show that Van Hove analysis provides a sensitive test for the OPE model.
DEDUCED FROM PRONG CROSS SECTIONS NORMALIZED USING THE DATA OF K. J. FOLEY ET AL., PRL 19, 330 (1967).
No description provided.
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.
Electron-proton elastic scattering cross sections have been measured to determine the proton electromagnetic form factors at squared four-momentum transfers q 2 between 10 and 50 fm −2 . At these values of q 2 we measured angular distributions between 25° and 110° and in addition at 25° and 35° cross sections for q 2 from 2 to 20 fm −2 using the external electron beam of the Bonn 2.5 GeV electron synchrotron. Our results confirm deviations from the scaling law.
Axis error includes +- 2/2 contribution (NORMALIZATION ERROR).
Axis error includes +- 2/2 contribution (NORMALIZATION ERROR).
Axis error includes +- 2/2 contribution (NORMALIZATION ERROR).
Production of B(1235) and ρ(1710) mesons is observed in the four-pion decay modes π+π+π−π0 in 16−GeVc π±p collisions. Decay distributions and branching fractions into various modes are presented. Absence of the two-pion mode π−π0 for the ρ(1710) is noted.
No description provided.
Polarization and differential cross-section data at 16 momenta between 0.86 and 2.74 GeV/ c are presented. (Preliminary data on some of the momenta have been published earlier.) In an energy-independent phase-shift analysis from threshold up to 2.5 GeV/ c , resonant-like as well as non-resonant solutions are found for the P 3 wave. An helicity flip-non-flip decomposition of the partial waves partly supports the indications found in the analyses of other reactions that the pomeron is built up mainly from s -channel helicity non-flip contributions.
No description provided.
No description provided.
No description provided.
We report on coherent interactions in a 2.5 event/μb K − d exposure. The predominant channel studied is K − d → K − π + gp − d (415 events). We find strong Q- and L-production in the (K ππ ) system. The production mechanism determines I = 1 2 for both enhancements and a spin-parity in the series 0 − , 1 + ,2 − … . A spin-parity analysis shows the Q to be a 1 + object, while the L is 1 + or 2 − , although a higher spin cannot be excluded. The cross sections for Q and L production and other final states are presented.
CORRECTED FOR UNSEEN RECOIL DEUTERONS BY EXTRAPOLATION. (UNCORRECTED CROSS SECTIONS ARE THOSE OBSERVED WITH P(DEUT) > 140 MEV/C).
Joint decay distributions have been studied in the reaction K + p → K ∗o (1420)Δ ++ at 5.0 GeV/ c in the transversity spin reference frame. Two alternative spin-parity assignments 2 + and 3 − for the K ∗ resonance have been considered and a comparison with the quark-model predictions has been made. The predictions of the quark model are equally well satisfied by the experimental results for both the 2 + and 3 − spin-parity assignments.
No description provided.
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