The target asymmetry T = ( σ ↑ − σ ↓)/( σ ↑ + σ ↓) for the reaction γ p → π + n has been measured at the Bonn 2.5 GeV electron synchrotron for a pion c.m. angle of 40° and γ energies between 0.5 and 2.2 GeV. Butanol was used as the target material. About 35% of the protons could be polarized using the dynamic-polarization method in a continuous-flow cryostat operating at 1°K and 25 kG. The π + mesons were detected in a magnetic-spectrometer system. Considerable structure in the asymmetry was observed.
Axis error includes +- 11/11 contribution.
The K − p reactions leading to charge exchange and hyperon final states have been studied at nine momenta between 862 and 1001 MeV/ c using data from a 600 000 picture exposure of the Lawrence Berkeley Laboratory 25″ liquid hydrogen bubble chamber. Partial cross sections are determined for all final states resolved by kinematic fitting. In addition, differential cross sections are presented for the two-body final states K o n , Λπ o and Σ +- π -+ along with hyperon polarization angular distributions for Λπ o and Σ + π − .
No description provided.
No description provided.
No description provided.
The results are presented of two partial-wave analyses of the (3π) − system in 30 000 events of the reaction π − p → π − π − π + p at 11.2 GeV/ c . Both techniques incorporate the assumptions of the isobar model and are (a) the University of Illinois program which fits in terms of the (3π) density matrix elements and (b) an amplitude parametrisaton including possible effects of both spin non-flip and spin flip at the baryon vertex. The results obtained with these independent programs are found to be very close.
NORMALIZED TO A TOTAL REACTION CROSS SECTION OF 1.17 +- 0.24 MB. ALL QUOTED CROSS SECTIONS ARE FOR INTEGRATED BREIT-WIGNERS.
A2 2+D-WAVE FOR 1.2 < M(3PI) < 1.4 GEV. THE FIRST THREE COMBINATIONS OF DENSITY MATRIX ELEMENTS ARE FOR NATURAL PARITY EXCHANGE, AND THE REMAINDER UNNATURAL.
The reaction pp→ π + d was studied at incident proton energies of 398, 455, 497, 530 and 572 MeV. Measurements of dσ/dΩ at 455 and 572 MeV show the presence of pion d-waves in the pion-deuteron system. Asymmetry measurements yield similar conclusions. Total cross-section measurements agree with recent fits to earlier data.
NORMALIZED TO 4.38 MB/SR AT THETA = 13.19 DEG FOR P P ELASTIC.
NORMALIZED TO 4.68 MB/SR AT THETA = 13.35 DEG FOR P P ELASTIC.
NORMALIZED (RELATIVE ERROR 2.1 PCT) TO THE DATA OF RICHARD-SERRE ET AL., NP B20, 413 (1970) (ABSOLUTE SCALE UNCERTAINTY 4.5 PCT).
Polarization in π−p elastic scattering, with emphasis in the region around the secondary dip and also θc.m.=90°, has been measured at 2.93 and 3.25 GeV/c. We observe an interesting sign change in this angular region.
No description provided.
No description provided.
Λ∘ polarization in inclusive production by protons on iridium has been measured at 28.5 GeV/c over the region 0.55 GeV/c<~P⊥<~1.6 GeV/c. The polarization rises from (-12.6±5.5)% at 0.55 GeV/c to (-33.4±4.6)% at 1.6 GeV/c. Significant differences from previous measurements at other energies with different targets are observed, particularly at low P⊥.
No description provided.
We have made, for the first time, a direct reconstruction of the pp elastic-scattering matrix at 579 MeV from a series of experiments performed at the Schweizerisches Institut für Nuklearforschung polarized-beam line. Fifteen observables consisting of the polarization, two-spin correlation and transfer parameters, and three-spin parameters were measured at seven angles between 66° and 90° (c. m.). The experimental results and reconstructed amplitudes are presented and compared to phase shift analysis.
No description provided.
VALUES OF PRECESSION ANGLE O. OBSERVABLES ARE RELATED BY THE FORMULA, (OABC) = (S'ABC)*COS(O) + (K'ABC)*SIN(O).
The polarization parameter in pn elastic scattering has been measured at 24 GeV/ c over the range of four-momentum transfer squared 0.1 < | t | < 1.25 (GeV/ c ) 2 , and found to be negative except for a zero at | t | = 0.65 (GeV/ c ) 2 .
No description provided.
Results from a partial wave analysis of theKππ system produced in the hypercharge exchange reaction π−p→(K+π−π0)Λ at 3.95 GeV/c are presented. SignificantQ1 production is observed but no evidence is found forQ2 production thus confirming the results obtained in a previous decay Dalitz plot analysis of the same reaction. The relative phase behaviour of the 1+(Kϱ) partial waves obtained with the present analysis provides additional confirmation of the resonance interpretation of theQ1 enhancement. Information is also obtained about its production properties and the role played by the Λ polarization in the hypercharge exchange reaction. This is compared with the results obtained in the reactionK−p→(π+π−π0)Λ at 4 GeV/c.
LAMBDA POLARIZATION CALCULATED AS AVERAGE POLARIZATION OF ALL 1 + (K RHO0) PARTIAL WAVES IN THE QLOW(1240) REGION.
SPIN PARITY CONTENT OF (K PI PI) SYSTEM.
CONTRIBUTION TO THE TOTAL JP=1+ INTENSITY FROM THE K* AND RHO ISOBARS.
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.
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