Excitation functions of the analyzing power in elastic proton-proton scattering from 0.45 to 2.5 GeV

Excitation functions A_N(p_lab,_c.m.) of the analyzing power in elastic proton-proton scattering have been measured in an internal target experiment at the Cooler Synchrotron COSY with an unpolarized proton beam and a polarized atomic hydrogen target. Data were taken continuously during the acceleration and deceleration for proton kinetic energies T_lab (momenta p_lab) between 0.45 and 2.5 GeV (1.0 and 3.3 GeV/c) and scattering angles 30 ^° _c.m. 90^°. The results provide excitation functions and angular distributions of high precision and internal consistency. The data can be used as calibration standard between 0.45 and 2.5 GeV. They have significant impact on phase shift solutions, in particular on the spin triplet phase shifts between 1.0 and 1.8 GeV.     

Excitation functions of the analyzing power in pp--> scattering from 0.45 to 2.5 GeV

Excitation functions A(N)(p(p),Theta(c.m.)) of the analyzing power in pp--> elastic scattering have been measured with a polarized atomic hydrogen target for projectile momenta p(p) between 1000 and 3300 MeV/ c. The experiment was performed for scattering angles 30 degrees 相似文献   

Elastic and inelastic effects in proton-proton scattering from states of pure spin

Modified phase-shift analyses of pp scattering are presented at p_L = 1.25 and 1.66 GeV/c and shown to give large negative elastic effects in Δσ_L^tot. Using a combination of phase-shift analyses from low energies up to 1.66 GeV/c and simple models of both elastic (pp → pp) and inelastic (pp → NΔ) scattering we conclude that the measured behaviour of Δσ_T^tot is mostly inelastic, but the large negative value of Δσ_L^tot is predominantly elastic with fluctuations produced by inelastic effects. We find no evidence for a dibaryon resonance.     

Elastic scattering of 0.8 GeV polarized protons from 46,48Ti

Differential cross sections and analyzing powers for elastic scattering of 800 MeV polarized protons from ^46,48Ti have been measured at laboratory angles ranging between 4° and 21°. The data are analyzed within the spin-dependent KMT formalism. Neutron density distributions are extracted and compared with the results of other experiments and with theoretical predictions. Disagreements between empirical results and DME calculations are found.     

Elastic proton scattering from 4He at 0.58 and 0.72 GeV

The energy spectra of α-particles recoiling from a ⁴He gas target bombarded by 0.58 and 0.72 GeV protons have been measured to obtain the differential cross sections for elastic scattering $\text{d}{}_{\mathrm{\sigma }}\text{d}{}_{\mathrm{t}}$, in the region of four-momentum transfer squared, ?t=0.13 ? 0.55 (GeV/c)². The experiment was designed especially to observe the region between the first and second diffraction maxima.     

Elastic antiproton-deutron scattering below 1.0 GeV/c

We present differential cross sections for elastic $\text{p}$d scattering at beam momenta 0.735 and 0.940 GeV/c and momentum transfers in the range 0.04<|t|<0.5(GeV/c)². The $\text{p}$d elastic differential cross section is expressed in terms of a deutron form factor and the I=0 t-channel exchange $\text{N}$N amplitudes, enabling us to isolate the corresponding I=0 t-channel exchange cross sections.     

Rapidity spectra in proton-proton and proton-antiproton scattering up to 540 GeV in a dual parton model

Some recent data at the ISR and SPS colliders are discussed in terms of a multi-pomeron exchange model formulated in the dual parton framework. Charged particle rapidity distributions, energy dependence of the central plateau, ratio of particle densities in proton-proton and antiproton-proton scattering and non-diffractive multiplicities are successfully accounted for in the model.     

Polarization in proton-proton elastic scattering at 10, 14 and 17.5 GeV/c

Data on the polarization parameter in pp elastic scattering in the |t|-range from ∼0.1 to ∼ 2.9 (GeV/c)² and at 10, 14 and 17.5 GeV/c are presented.     

A novel treatment of the proton-proton Coulomb force in proton-deuteron Faddeev calculations: Elastic scattering

We propose a novel approach to incorporate the proton-proton (pp) Coulomb force into the three-nucleon (3N) Faddeev calculations. The main new ingredient is a 3-dimensional screened pp Coulomb t -matrix obtained by a numerical solution of the 3-dimensional Lippmann-Schwinger (LS) equation. We demonstrate numerically and provide analytical insight that the elastic proton-deuteron (pd ) observables can be determined directly from the resulting on-shell 3N amplitude increasing the screening radius. The screening limit exists without the need of renormalisation not only for observables but for the elastic pd amplitude itself.     

Elastic scattering of 1 GeV protons from nuclei as a test for flucton model

Cross sections for elastic scattering of 1 GeV protons from⁴⁰Ca nuclei have been calculated using the flucton model. The influence of the collective flucton nuclaon correlations on the calculated cross sections is examined. The calculated cross sections are in significant disagreement with the experimental data. This may be considered as an argument against the flucton model.     

Large t elastic proton-proton scattering at √s = 53 GeV

New experimental results are presented on proton-proton elastic scattering in the range of momentum transfer 0.8GeV² < ?t < 9 GeV² at a centre-of-mass energy of √s = 53 GeV. The data are obtained sing the Split-Field- Magnet Detector at the CERN Intersecting Storage Rings. The cross section has well-known minimum at ?t = (1.34±0.02) GeV² but no further minimum or change of slope is observed between 2 and 6.5 GeV².     

The real part of the amplitude of proton-proton scattering at an energy of 3 GeV

Measurement of the differential cross-sections of proton-proton scattering at an energy of 3 GeV is described. The measurement was performed in the region of angles from 2·4° to 16·2°. Analysis of the experimental data shows that besides the imaginary scattering amplitude a real part is also necessary in order to describe elastic scattering at an energy of 3 GeV; the magnitude of the real part is 24% of the magnitude of the imaginary part.It is the authors' pleasant duty to thank V. Sviridov, V. Nikitin, M. afranova and L. Kirillova from the High Energy Laboratory of the Joint Institute of Nuclear Research in Dubna for their help in irradiating the emulsions and monitoring the primary proton beam, and also to Prof. V. Petrílka for stimulating interest and suport in the work.     

Measurement of the polarization parameter in small angle proton-proton elastic scattering at 6 GeV/c

The polarization parameter in pp elastic scattering was measured at 6 GeV/c with fine t resolution for 0.02 < ?t < 0.5 GeV² using a polarized proton beam with Effective Mass Spectrometer at the Zero Gradient Synchrotron. The polarization rises like √?t in the interval 0.02 < ?t < 0.1 GeV², No statistical significant structure was found in this region of momentum transfer.     

Hadron production at transverse momenta from 0.5 up to 2.2 GeV/c in proton-proton collisions at 70 GeV

The cross sections for π^±, K^±, p, and $\text{p}$ production in pp collisions have been measured at transverse momenta from 0.48 up to 2.21 GeV/c at 70 GeV. The data are compared with results obtained at lower and higher proton energies and also with the quantum chromodynamics parton model (QPM) calculations. Common behaviour of the cross sections of the form $\text{g(p}{}_{\mathrm{\perp }}\text{)?(x}{}_{\mathrm{\perp }}\text{)}$ in the energy range above 200 GeV does not take place at lower energies. Qualitatively QPM fits the data and the best agreement is for π⁺/π^? and K⁺/π⁺ ratios.     

Correlations in quasi-elastic proton-proton scattering at total c.m. energies of 23 and 31 GeV

Data are reported on angular and rapidity (η) distributions of a charged particle c produced in quasi-elastic proton-proton scattering (p+p→p+c+anything) at the CERN ISR.     

Measurement of spin-correlation parameters ANN,ASS, and ASL at 2.1 GeV in proton-proton elastic scattering

At the Cooler Synchrotron COSY/Jülich spin-correlation parameters in elastic proton-proton (pp) scattering have been measured with a 2.11 GeV polarized proton beam and a polarized hydrogen atomic beam target. We report results for A(NN), A(SS), and A(SL) for c.m. scattering angles between 30 degrees and 90 degrees. Our data on A(SS)--the first measurement of this observable above 800 MeV--clearly disagrees with predictions of available pp scattering phase-shift solutions while A(NN) and A(SL) are reproduced reasonably well. We show that in the direct reconstruction of the scattering amplitudes from the body of available pp elastic scattering data at 2.1 GeV the number of possible solutions is considerably reduced.     

Neutron-proton elastic scattering from 10 to 70 GeV/c

The neutron-proton elastic differential cross section has been measured for incident momenta between 10 and 70 GeV/c and for values of the momentum transfer squared between 0.1 and 2.8 (GeV/c)². The forward peak and the break at about ∣t∣ = 1 (GeV/c)² are very similar to corresponding pp data.     

Neutron-proton charge-exchange scattering from 8 to 29 GeV/c

The differential cross sections for neutron-proton charge-exchange scattering have been measured for incident neutron momenta between 8 and 29 GeV/c and for four-momentum transfers |t| between 0.002 and 1.0 (GeV/c)². A neutron beam with a broad momentum spectrum was scattered from a liquid hydrogen target. The momenta and scattering angles of the forward-scattered protons were measured by a spark-chamber magnet spectrometer. The flight times and scattering angles of the recoil neutrons were measured by a bank of thick scintillation counters. The efficiencies of the neutron counters were determined in a separate measurement. Absolute normalization of the data was obtained from a measurement of the diffraction dissociation of neutrons from carbon nuclei. Differential cross sections, based on ～ 23 000 events, are presented for 9 different momenta. The shape of the differential cross sections and the momentum dependence are examined in detail.