A measurement of the polarization parameter P 0 in pp elastic scattering has been made at 24 GeV/ c over the range | t | = 0.1 to 0.9 (GeV/ c ) 2 , positive, falling to zero around | t | = 0.8 (GeV/ c ) 2 . For the range 0.1 ⪕ |t| ⪕ 0.4 GeV /c) 2 , P 0 is constant at about 0.03.
Axis error includes +- 5/5 contribution (SYS-ERR DUE MAINLY TO UNCERTAINTY IN KNOWLEDGE OF ABSOLUTE VALUE OF TARGET POLARIZATION).
The polarization parameter in proton-proton elastic scattering has been measured at an incident momentum of 7.9 GeV/ c and four-momentum transfers in the range 0.9 < | t | < 6.5 (GeV/ c ) 2 using a high intensity unpolarized proton beam incident on a polarized proton target. The angle and momentum of the forward scattered protons were measured with a magnet spectrometer and scintillation counter hodoscopes and the angle of the recoil proton was measured using similar hodoscopes. A clean separation between the elastic scattering from free hydrogen and that coming from inelastic interactions and from interactions with complex nuclei in the target was obtained. The polarization shows substantial structure rising from zero at | t | = 1.0 (GeV/ c ) 2 to a maximum at | t | = 1.7 (GeV/ c ) 2 and then falling to zero at | t | = 2.0 (GeV/ c ) 2 . There is evidence of a further peak at | t | = 2.8 (GeV/ c ) 2 . Above | t | = 3.25 (GeV/ c ) 2 the polarization is small and consistent with zero. A comparison of these data with data obtained at other beam momenta shows that the polarization parameter has a strong momentum dependence.
No description provided.
The pp analyzing power was measured using the SATURNE II polarized proton beam and the Saclay frozen spin polarized target. The measurements at 0.88 and 1.1 GeV were carried out in the angular region θ CM from 28° to ≅50° and complete our previous measurements from 45 ° to 90°. Above 1.1 GeV the measurements presented here cover both regions, extending from θ CM = 28° (at the lower energies) or θ CM = 18° (at the higher energies) to θ CM > 90°. The shape of the angular distribution A oono ( pp ) = ƒ(θ CM ) changes considerably with increasing energy. The new data show the onset of a characteristic t -dependence of the analyzing power, with a minimum at − t ≅ 1.0 (GeV/ c ) 2 followed by a second maximum at − t ≅ 1.5 (GeV/ c ) 2 . This structure is present at all energies, from kinematic threshold to 200 GeV.
Errors are statistical plus random-like instrumental uncertainties. Results using polarised target.
Errors are statistical plus random-like instrumental uncertainties. Results using polarised target.
Errors are statistical plus random-like instrumental uncertainties. Results using polarised target.
A measurement of the polarization parameter P 0 in pp elastic scattering has been made at 24 GeV/ c over the range of momentum transfer squared 0.7 < | t | < 5.0 (GeV/ c ) 2 . The structure of P 0 has changed compared to typical lower energy data. The second peak is suppressed and a dip has appeared at | t | = 3.6 (GeV/ c ) 2 .
No description provided.
In an experiment at the Argonne Zero-Gradient Synchrotron we have measured values of the polarization parameter P(t) in the elastic scattering of negative pions, positive pions, positive kaons, and protons on protons at several incident laboratory momenta from 2.50 to 5.15 GeVc, and for values of the momentum transfer variable −t from 0.2 to 2.0 (GeVc)2. The final results from p−p elastic scattering presented here extend our knowledge of the polarization to much larger values of −t than the results of previous measurements. Outstanding features revealed by these polarization data include (1) the development of a dip at about −t=0.7 (GeVc)2, with (2) a substantial secondary peak at larger values of −t and (3) the gradual diminution of the maximum polarization with increasing energy. It is possible to fit the t dependence of the experimental results with a simple model. The energy dependence of the polarized cross sections is also discussed.
No description provided.
No description provided.
No description provided.
Measurements of the polarization in pp elastic scattering have been made at 5.15 GeV/c over the range −t=0.2 to 1.8 (GeV/c)2. The data are compared with a Regge-pole model, and with the diffraction model of Durand and Lipes in which the absorptive part of the pp interaction is derived from the electromagnetic form factor of the proton. The latter model reproduces the t dependence of the experimental data in a qualitative way.
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The analyzing power AN of proton-proton elastic scattering in the Coulomb-nuclear interference region has been measured using the 200-GeV/c Fermilab polarized proton beam. A theoretically predicted interference between the hadronic non-spin-flip amplitude and the electromagnetic spin-flip amplitude is shown for the first time to be present at high energies in the region of 1.5 × 10−3 to 5.0 × 10−2 (GeV/c)2 four-momentum transfer squared, and our results are analyzed in connection with theoretical calculations. In addition, the role of possible contributions of the hadronic spin-flip amplitude is discussed.
No description provided.
The accelerated polarized deuteron beam of Saturn II was used to measure the analyzing power for np elastic scattering at five energies. The left-right asymmetries ε = (L + R)/(L + R) for np and for pp elastic scattering were measured simultaneously by CH 2 − carbon subtraction using one of the beam-line polarimeters. The analyzing power A 00 n 0 (np) is given by the ratio ε np d / ε pp d multiplied by the known analyzing power for pp elastic scattering. Experimental evidence is consistent with the underlying assumption that in the kinetmatic region of the experiment the ratio of the np to pp analyzing powers for scattering of quasifree nucleons in deuterons is the same as for scattering of free neutrons and protons, respectively.
No description provided.
No description provided.
No description provided.
Excitation functions AN(pp,Θc.m.) of the analyzing power in pp→ elastic scattering have been measured with a polarized atomic hydrogen target for projectile momenta pp between 1000 and 3300 MeV/ c. The experiment was performed for scattering angles 30°≤Θc.m.≤90° using the recirculating beam of the proton storage ring COSY during acceleration. The resulting excitation functions and angular distributions of high internal consistency have significant impact on the recent phase shift solution SAID SP99, in particular, on the spin triplet phase shifts between 1000 and 1800 MeV, and demonstrate the limited predictive power of single-energy phase shift solutions at these energies.
No description provided.
No description provided.
No description provided.
The polarization parameter in proton-proton scattering has been measured at incident proton kinetic energies of 1.7, 2.85, 3.5, 4.0, 5.05, and 6.15 BeV and for four-momentum transfer squared between 0.1 and 1.0 (BeV/c)2. The experiment was done with an unpolarized proton beam from the Bevatron striking a polarized proton target. Both final-state protons were detected in coincidence and the asymmetry in counting rate for target protons polarized parallel and antiparallel to the scattering normal was measured. The maximum polarization was observed to decrease from 0.4 at 1.7 BeV to 0.2 at 6.1 BeV. The maximum of the polarization at all energies studied occurs at a four-momentum transfer squared of 0.3 to 0.4 (BeV/c)2.
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