The angular distributions of the analyzing power for the pp → dπ + reaction have been measured at seven energies T p = 1.2, 1.4, 1.6, 1.7, 1.8, 2.0 and 2.3 GeV. The data show a strong energy dependence with a structure centered at √ s π d = 2.66 GeV. Possible interpretations are presented in the frame of the OPE model and involving the question of the excitation of a dibaryon resonance.
No description provided.
No description provided.
No description provided.
A precision measurement of the angular distribution of the analyzing power of the reaction p + p → d + π + has been made at 0.8 GeV. It is shown that none of the existing theoretical calculations, including those which introduce resonant dibaryon amplitudes, reproduce even the qualitative features of the data. It is concluded that our data do not require dibaryon admixtures of the kind proposed for the interpretation of recent data on vector analyzing power, i T 11 (θ), of π− d elastic scattering at the same center of mass energy.
LOWER ENERGY DATA NOT IN PUBLICATION.
LOWER ENERGY DATA NOT IN PUBLICATION.
LOWER ENERGY DATA NOT IN PUBLICATION.
Forward differential cross sections for isospin-1 bosons produced in p+p→d+x+ were measured using a deuteron missing-mass spectrometer at a small angle between 4.0- and 12.3−GeVc incident momentum. Differential cross sections for π+ and ρ+ were extracted from the spectra using phase-space backgrounds. They range from 10.4 to 0.4 μb/sr for π+ and from 1.4 to 0.3 μb/sr for ρ+. A bump near 6 GeVc appears in both dπ and dρ channels. No clear evidence is seen for higher-mass bosons. The possible δ+ cross sections average less than 0.01 μb/sr.
TECHNIQUE USED...ELECTRONIC. TABLE 1.
TECHNIQUE USED...MISSING MASS. BREIT WIGNER USED WITH FIXED WIDTH (150 MEV) AND VARIABLE MASS (LATTER VARIED WITH MOMENTA FROM 715 TO 765 MEV). 6 PERCENT NORMALIZATION ERROR; 20 PERCENT FROM BREIT WIGNER FIT. TABLE 1.
TECHNIQUE USED...MISSING MASS. CROSS-SECTIONS CORRESPOND TO VERY NARROW DELTA (962).
The present data support a large anisotropy in accordance with phase shift predictions and in contrast to another recent experiment.
Measured deuteron angular distribution in the c.m. system. The errors shown are statistical only and there is an additional 10 PCT systematic uncertainty on the overall normalisation.
Legendre polynomial coefficients from a second order and fourth order fit.
Total cross section from second order fit.
Results are presented from an experiment in which high-energy deuterons, produced by proton-proton interactions at 21.1 GeV/ c incident momentum, were detected over a range of angles from 12.5 mrad to 60 mrad in the laboratory system. From the momentum spectra of the deuterons, the final states D + π + and D + ϱ + have been identified. The angular distribution for these reactions are presented and compared with previous data at lower energies.
The statistical errors are presented.
The statistical errors are presented.
The statistical errors are presented. The data are from previous publications.
Precision measurements of the analyzing powers for the reaction ppol+p→d+π+ have been made at ≃ 550, 600, 650, 700, and 800 MeV. The data have been analyzed in terms of Legendre polynomials. It is found that excitation functions for both even and odd Legendre coefficients exhibit very similar resonant behaviors. It is concluded that the triplet amplitudes are as strongly dominated by the Δ(1232) as the well-known singlet amplitude, D21, and that the data do not exhibit any anomalous behavior suggestive of dibaryon resonances.
No description provided.
Inclusive measurements of the pion differential cross sections and analyzing powers have been carried out for the pp→pnπ+ reaction at 420 and 500 MeV using the SASP spectrometer at TRIUMF. Pion energies from the onset of the continuum down to about 25 MeV were covered in the angular range from 23° to 100° (lab). Total cross sections of 0.750±0.075 mb and 2.77±0.28 mb were determined for the pp→pnπ+ reaction at 420 and 500 MeV, respectively. The experimental results are presented and discussed within the framework of a partial wave analysis. Theoretical predictions from a covariant one-boson-exchange model that includes final state interactions, provide a good description of the data. The pion spectra, in the region corresponding to low relative np energies, are also well described by a final state interaction model that uses the pp→dπ+ cross sections as input. Details of the determination of the background corrections and detector efficiencies will be discussed.
No description provided.
Only statistical errors are given.
Only statistical errors are given.
The three polarization tensor components of the deuteron produced in the H( p , d )π + reaction have been measured for the first time. The experiment was performed using a vertically polarized proton beam produced by the SATURNE accelerator. The deuteron polarization was measured with the POLDER polarimeter. The three polarizing powers t 20 00 , t 21 00 and t 22 00 and the three spin-transfer observables t 20 11 , t 22 11 and t 22 11 have been extracted at a proton kinetic energy of 580 MeV over a wide angular range and at two fixed center-of-mass angles, 132° and 151°, between 800 and 1300 MeV. The six observables, calculated in the C.M. helicity frame, have been compared with predictions of the most refined partial-wave analyses and also with the predictions of a theoretical coupled-channel model which includes the NN-NΔ transition. The comparison between the data and the theory/partial-wave analyses shows some discrepancies which get worse with increasing proton energy. Adding these data to the world database should improve significantly future partial-wave analyses. The A y 0 analyzing power has also been measured over the same kinematical range. The partial-wave analysis predictions are in good agreement with this observable.
No description provided.
No description provided.
No description provided.
We have measured angular distributions of differential cross sections and analyzing powers ( A y ) of the reaction p p → d π + at six incident proton energies between 1.3 and 2.4 GeV. They confirm the rapid variations at √ s = 2.65 GeV suggested by earlier experiments. Deviations from a monotonic behavior are also found in the excitation functions of the differential cross section at t = 0 or where Θ π + (c.m.) = 0°. Structures clearly appear at √ s = 2.4 and 2.65 GeV, in some coefficients of the associated Legendre function expansions of A y .
No description provided.
No description provided.
No description provided.
Differential cross sections and polarization asymmetries for the reaction p + p → d + π + have been measured at 0.8 GeV. The data has been analyzed within the formalism of Mandl and Regge and the results are compared with the recent coupled channel calculations of Niskanen. It is concluded that at this energy the production of upto f-wave pions is important.
No description provided.
No description provided.
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