High-Energy Scattering Research Articles

The Unitarity Condition and High Energy Scattering

The Unitarity Condition and High Energy Scattering

Consistency Conditions on Models for High-Energy Scattering

From unitarity, analyticity in t, and analyticity in E, a variety of conditions can be derived for the high-energy behavior of a crossing symmetric two-body scattering amplitude F(E,t). These conditions are studied as consistency conditions for a class of models for high-energy scattering based on smoothly varying functions. For this class of models they lead to: (1) the Froissart bound without making explicit use of Martin's enlargement of the Lehmann ellipse, (2) conditions on the phase of the amplitude and its derivative with respect to t in the forward direction. As an example of the use of the phase conditions, it is shown how the Lehmann ellipse can be enlarged to give analyticity in the circle |t| < R, where R is fixed. Although the method is different, this result is closely related to the general results of Martin, but with our smoothness assumptions a little more detail can be stated about the behavior of F(E,t).

Composite Models of Hadrons and High Energy Scattering

Composite Models of Hadrons and High Energy Scattering

Regge Poles in High Energy Scattering

Regge Poles in High Energy Scattering

Quark Model and High Energy Scattering

Quark Model and High Energy Scattering

Composite Models of Hadrons and High-Energy Scattering

Composite Models of Hadrons and High-Energy Scattering

Quark Models, Universality, Symmetry, and High-Energy Scattering

New relations between meson-baryon and baryon-baryon cross sections are found by making use of predictions for scattering on deuteron targets. These are in better agreement with experiment than previously derived relations and provide a better parametrization for the quark-model amplitudes. They show that universal coupling of $\ensuremath{\omega}$ and $\ensuremath{\phi}$ Regge trajectories to mesons and baryons is a good approximation, but that the ratio of the two couplings is about 20% greater than predicted by SU(3) and SU(6).

Radiative Corrections to High-Energy Inelastic Electron Scattering

Radiative Corrections to High-Energy Inelastic Electron Scattering

Charge Independence in High-Energy Scattering from Deuterons

It is shown that the usual shadow correction for high-energy scattering of particles by deuterons violates charge independence in the case of pions. Alternative formulas are derived which are applicable to this case.

Quark Models and High-Energy Scattering

Quark Models and High-Energy Scattering

Small-Angle High-Energy Scattering by Deuterons

Small-Angle High-Energy Scattering by Deuterons

2+Mesons and High-Energy Scattering

<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>Mesons and High-Energy Scattering

High-Energy Elastic Scattering at Low Momentum Transfers

High-Energy Elastic Scattering at Low Momentum Transfers

Polarization in High-Energy Meson-Baryon Diffraction Scattering

Polarization in High-Energy Meson-Baryon Diffraction Scattering

An Optical Model for High-Energy Scattering

An attempt is made to show that the behavior of the diffraction width in high-energy scattering can be attributed to the presence of the inelastic threshold in one of the channels that dominates the process. The theory which originally concerns itself with $p\ensuremath{-}p$ diffraction scattering is a pure optical model. It starts with the assumption that high-energy scattering is dominated by inelastic processes and that the degree of inelasticity is determined by the overlap of the meson clouds surrounding the colliding particles. Three input parameters are introduced into the framework, viz. the inverse range of the nucleonic meson cloud $\ensuremath{\mu}$, the power $\ensuremath{\lambda}$ in the ansatz that we use to relate the overlap function with the transparency coefficient, and the cutoff mass ${\ensuremath{\mu}}_{i}$ which originates in the requirement that there be a minimal energy of local excitation in order that an inelastic process can take place. In this optical model we can identify $\ensuremath{\lambda}$ with the strength of the absorptive potential. We can fix these parameters by using the experimental data as follows: The limits ($\frac{{\ensuremath{\sigma}}_{\mathrm{el}}}{{\ensuremath{\sigma}}_{T}}$) and ${\ensuremath{\sigma}}_{T}$ at infinite-energy give the values of $\ensuremath{\lambda}$ and $\ensuremath{\mu}$, respectively, while ${\ensuremath{\mu}}_{i}$ is determined from the approach ${\ensuremath{\sigma}}_{T}(E)\ensuremath{\rightarrow}{\ensuremath{\sigma}}_{T}(\ensuremath{\infty})$ in the asymptotic region. With the appropriate values of the parameters we can predict the transient shrinkage of the diffraction width in $p\ensuremath{-}p$ and ${K}^{+}\ensuremath{-}p$ scattering and also the transient expansion of the diffraction width in $\overline{p}\ensuremath{-}p$ and ${K}^{\ensuremath{-}}\ensuremath{-}p$ scattering. We can also show that the widths of the diffraction peak in ${\ensuremath{\pi}}^{+}\ensuremath{-}p$ and ${\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{-}p$ scattering are almost energy-independent. The consequences of the application of the model on nondiffractive processes are the following: In large angle scattering the differential cross section tends to flatten with increasing momentum transfer. At relativistic energies the one-fourth-power law for the average multiplicity of the secondaries in Fermi's statistical theory is quenched by a logarithmic factor.

Phenomenological Approach to Explain the Behavior of the Diffraction Peak in High-Energy Scattering

It is pointed out that (i) the observed shrinkage of the diffraction peaks in both $p\ensuremath{-}p$ scattering and ${K}^{+}\ensuremath{-}p$ scattering does not necessarily correspond to the shrinkage predicted by Regge-pole theory, (ii) an upper limit to the width of the diffraction peak can be predicted from a theoretical point of view, and (iii) the observed widths of the diffraction peaks can be explained in terms of total cross sections and a parameter having the same value for various kinds of meson-nucleon scattering (similarly for nucleon-nucleon and nucleon-antinucleon scattering).

Method of Study of High-Energy Scattering Events with Very Small Energy Losses

Method of Study of High-Energy Scattering Events with Very Small Energy Losses

Method of Study of High-Energy Scattering Events with Very Small Energy Losses

A method using an accelerator and thin targets is suggested for investigating very small energy losses in highenergy electron or proton scattering events. (C.E.S.)

Polarization in High-Energy Inelastic Scattering

Spin-dependent distortion effects were studied in the Polarization produced in the excitation of the 2/sup +/ level of C/sup 12/ at 4.43 Mev. (R.E.U.)

High-Energy Scattering Amplitude in Perturbation Theory

The consequences of keeping terms in addition to the leading terms in each order of perturbation theory are investigated. The model is the $g{\ensuremath{\phi}}^{3}$ theory and the method is that of Bjorken and Wu. When the second-most dominant terms in each order of ladder graphs are summed, a second-order pole in the angular momentum plane is obtained and the contribution to the amplitude dominates the sum of leading terms at high energy. When the class of terms to be summed is further enlarged in a well-defined way, the simple Regge behavior is restored. The divergence at threshold in the trajectory function obtained by summing the leading terms is not present in the final result. The question of the high-energy behavior of the complete sum of the ladder graphs is still unsettled.