Differential cross sections and polarization analyzing powers for proton-deuteron elastic scattering have been measured at 800 MeV incident proton kinetic energy over the range of center-of-mass angles from 14.1° to 153.6°. The differential cross sections are described by the Glauber theory of impulse approximation at forward angles (−t<0.5) and exhibit the exponential dependence on cosθc.m. typical for these energies at backward angles (cosθc.m.<−0.5). The analyzing power shows considerable structure with strong positive peaks at forward and backward angles and a sharp dip at t=−0.4 typical at intermediate energies. There is no evidence for correspondence of the angular dependence of the analyzing power with that for the pp→dπ+ reaction. At large momentum transfer the data favor calculations based on multiple scattering with a modified deuteron form factor rather than N* exchange. NUCLEAR REACTIONS H2(p,p)H2, E=800 MeV, measured σ(θ) and Ay(θ).
No description provided.
We report the measurement of the differential cross section of the reaction γ +p→π0 +p at a photon energy of 1.4 GeV and pion c.m. angles between 60 and 175 degrees. The angular distribution confirms the simple quark model prediction of a pure magnetic excitation of theF37 (1950) resonance.
No description provided.
Radiation capture of π − on hydrogen has been measured in the momentum range from p π − = 210 MeV/ c to p π − = 385 MeV/ c and for c.m. angles between 30° and 120°, covering the Δ (1232) resonance. The unambiguous separation of the events from the charge exchange background is based on precise neutron time-of-flight measurements. Detector efficiencies were carefully determined in separate experiments. The experimental results are in good agreement with those of the inverse reaction and with most recent multipole analyses. An upper limit of ±2% can be set on the contribution of the isotensor term to the transition amplitude. A time reversal violating phase, when added to the resonant M 1+ 3 amplitude in the Donnachie-Shaw model, is found to be consistent with zero.
This results was extracted from the cross sections for the inverse reactionPI- P --> GAMMA N via detailed balance by applying relation: D(SIG(GAMMA))/D(OM EGA)=D(SIG(PI-))/D(OMEGA)*P(PI)**2/2/P(GAMMA)**2.
At the Bonn 2.5 GeV electron synchrotron we have measured the differential cross section of the reaction γp→π0p at a pion CM angle of 170° and at photon energiesKγ between 0.6 and 1.8 GeV. In comparison to previous measurements the accuracy of the data was improved substantially. For the first time in neutral pion photoproduction a cusp structure at the η-threshold has been confirmed [1].
No description provided.
We present measurements from a counter-optical spark chamber experiment of the differential cross sections for p̄p → π 0 π 0 , π 0 η 0 at 25 momenta in the range 1.1 − 2.0 GeV/ c (c.m. energy 2.12 to 2.43 GeV). Approximately 750 000 pictures were taken in the experiment.
THE ANGULAR DISTRIBUTIONS IN THE PUBLISHED FIGURES ARE NOT TABULATED HERE SINCE THEY ARE ONLY RECONSTRUCTED FROM THE LEGENDRE EXPANSION COEFFICIENTS WHICH WERE MEASURED DIRECTLY FROM THE DATA.
No description provided.
LEGENDRE COEFFICIENTS NORMALIZED SO THAT LEG(L=0) = SIG/(2*PI) (IDENTICAL PARTICLES IN FINAL STATE). THESE ARE PLOTTED IN FIG. 1 OF THE FOLLOWING PAPER.
We present differential cross-sections for pp elastic scattering at eight laboratory momenta from 1.50 to 2.06 GeV/c. The data are analysed using an 8-parameter optical modelà la Frahn and Venter. However, the best representation of the differential cross-sections is obtained by combining the glory model with a parametrization of the scattering amplitude in terms of coherent exponentials. Both representations show the dominance of the partial wave with orbital angular momentum equal to four.
No description provided.
We present results on charged multiplicity nch=2 and nch>2 muon events produced in e+e− collisions with 〈s12〉=7.3 GeV at 90° to the beams. The background-subtracted inclusive cross section for the nch=2 events is 10.2±5.4 pb/sr, in agreement with the expected contribution from the heavy lepton τ. The cross section for the nch>2 events is 19.0±6.5 pb/sr whereas we expect only 2.9 pb/sr from the τ, indicating that we may be seeing the weak decays of charmed mesons.
No description provided.
No description provided.
The polarization parameter P for the reactions p p → π − π + and p p → K − K + has been measured over essentially the full angular range at ll laboratory momenta between 1.0 and 2.2. GeV/ c , using a proton target polarized perpendicular to the scattering plane. The angles and momenta of both final state particles were determined from wire spark chambers, using the deflection caused by the polarized target magnet. Between 1000 and 5300 π − π + events, and 140 and 1300 K − K + events, were measured at each momentum. Differential cross sections for p p → π − π + were obtained. These are in excellent agreement with previous results. The polarization parameter for both channels is very close to +1 over much of the angular range. Legendre polynomial fits to the data are presented.
THE DIFFERENTIAL CROSS SECTIONS IN THIS EXPERIMENT AGREE WITH THE ONES FROM THE AUTHORS' EARLIER EXPERIMENT (E. EISENHANDLER ET AL., NP B96, 109(1975)) USING A LIQUID HYDROGEN TARGET, THOUGH THEY DO NOT CONSIDER THE PRESENT ONES QUITE AS RELIABLE.
No description provided.
No description provided.
Qausi-elastic ω production by ep scattering in the kinematic region 0.3. < Q 2 < 1.4 GeV 2 and 1.7 < W < 2.8 GeV was studied using a streamer chamber at DESY. The production angular distribution for γ V p → ω p has a strong non-peripheral component for W < 2 GeV. The ω production cross section falls by a factor of 4 as W changes from 1.7 to 2.8 GeV. In contrast the cross section for ω production with | t | < 0.5 GeV 2 is W independent between 1.7 and 2.8 GeV and for W > 2.0 GeV consistent in both W and Q 2 dependence with the predictions of a model based on one-pion exchange and diffraction.
FOR ALL T-VALUES. THE GAMMA* P TOTAL CROSS SECTION WAS TAKEN FROM A FIT TO THE DATA OF S. STEIN ET AL., PR D12, 1884 (1975). 'PPD'.
'PPD'. PERIPHERAL OMEGA PRODUCTION.
No description provided.
Pion production on a CD2 target has been measured using the high-resolution magnetic spectrometer SPES I. Differential cross sections for the reaction D(p, π+)T have been determed at Tp=410, 605, and 809 MeV. The present data, together with previous results establish a complete angular distribution of the reaction D(p, π+)T at ∼ 600 MeV and the energy dependence of the differential cross section for this reaction at several constant momentum transfers.
No description provided.
No description provided.
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