Total Cross Sections and Slope of Regge Trajectories

A simple model for elastic diffractive hadron scattering, reproducing the dip-bump structure is used to analyze pp and [Formula: see text] scattering. The main emphasis is on the delicate and nontrivial dynamics in the dip-bump region, near t = -1 GeV 2. The simplicity of the model and the expected smallness of the absorption corrections enables one the control of various contributions to the scattering amplitude, in particular the interplay between the C-even and C-odd components of the amplitude, as well as their relative contribution, changing with s and t. The role of the nonlinearity of the Regge trajectories is scrutinized. The ratio of the real to imaginary parts of the forward amplitude, the ratio of elastic to total cross-sections and the inelastic cross-section are calculated. Predictions for the LHC energy region, where most of the existing models will be either confirmed or ruled out, are presented.

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Regge theory in a holographic dual of QCD in the Veneziano limit

Journal of High Energy Physics ◽

10.1007/jhep07(2021)065 ◽

2021 ◽

Vol 2021 (7) ◽

Author(s):

Artur Amorim ◽

Miguel S. Costa ◽

Matti Järvinen

Keyword(s):

Cross Sections ◽

Holographic Model ◽

Meson Spectrum ◽

Total Cross Sections ◽

Regge Theory ◽

Regge Trajectories ◽

Pseudoscalar Mesons ◽

Higher Spin ◽

Spin Fields ◽

The Masses

Abstract We initiate the study of Regge theory in a bottom-up holographic model for QCD in the Veneziano limit, where the backreaction of the quarks to the gluon dynamics is included. We determine the parameters of the model by carrying out a precise fit to the meson spectrum in QCD. The spectrum for spin-one and pseudoscalar mesons is well reproduced. We then generalise the model to incluce higher spin fields in the bulk trajectories dual to the Pomeron and meson Regge trajectories at the boundary. With this setting, we fit the masses of the mesons with spins J = 2, 3, and 4, as well as the experimental data of the total cross-sections σ(γγ → X), σ(γp → X) and σ(pp → X). For the cross sections we obtain a $$ {\chi}_{\mathrm{d}.\mathrm{o}.\mathrm{f}}^2 $$ χ d . o . f 2 of 0.74 for a total of 199 experimental points.

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Analysis of STEM micrographs of thick objects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081395 ◽

1978 ◽

Vol 36 (2) ◽

pp. 106-107

Author(s):

S. Golladay

Keyword(s):

Inelastic Scattering ◽

Multiple Scattering ◽

Mass Distribution ◽

Cross Sections ◽

Phase Contrast ◽

Image Point ◽

Contrast Effects ◽

Total Cross Sections ◽

Elastic And Inelastic Scattering

The theory of multiple scattering has been worked out by Groves and comparisons have been made between predicted and observed signals for thick specimens observed in a STEM under conditions where phase contrast effects are unimportant. Independent measurements of the collection efficiencies of the two STEM detectors, calculations of the ratio σe/σi = R, where σe, σi are the total cross sections for elastic and inelastic scattering respectively, and a model of the unknown mass distribution are needed for these comparisons. In this paper an extension of this work will be described which allows the determination of the required efficiencies, R, and the unknown mass distribution from the data without additional measurements or models. Essential to the analysis is the fact that in a STEM two or more signal measurements can be made simultaneously at each image point.

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Production Cross Sections of Fragments from Beams of 400–650 MeV per Nucleon9Be,11B,12C,14N,15N,16O,20Ne,22Ne,56Fe, and58Ni Nuclei Interacting in a Liquid Hydrogen Target. I. Charge Changing and Total Cross Sections

The Astrophysical Journal ◽

10.1086/306445 ◽

1998 ◽

Vol 508 (2) ◽

pp. 940-948 ◽

Cited By ~ 34

Author(s):

W. R. Webber ◽

J. C. Kish ◽

J. M. Rockstroh ◽

Y. Cassagnou ◽

R. Legrain ◽

...

Keyword(s):

Cross Sections ◽

Production Cross ◽

Liquid Hydrogen ◽

Liquid Hydrogen Target ◽

Hydrogen Target ◽

Total Cross Sections

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Total cross sections of eγ → $$ eX\overline{X} $$ processes with X = μ, γ, e via multiloop methods

Journal of High Energy Physics ◽

10.1007/jhep01(2021)144 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Roman N. Lee ◽

Alexey A. Lyubyakin ◽

Vyacheslav A. Stotsky

Keyword(s):

Cross Section ◽

Cross Sections ◽

Elliptic Integral ◽

High Energy ◽

Calculation Methods ◽

Complete Elliptic Integral ◽

Total Cross Sections ◽

Multiloop Calculation ◽

The Cross ◽

Analytical Expressions

Abstract Using modern multiloop calculation methods, we derive the analytical expressions for the total cross sections of the processes e−γ →$$ {e}^{-}X\overline{X} $$ e − X X ¯ with X = μ, γ or e at arbitrary energies. For the first two processes our results are expressed via classical polylogarithms. The cross section of e−γ → e−e−e+ is represented as a one-fold integral of complete elliptic integral K and logarithms. Using our results, we calculate the threshold and high-energy asymptotics and compare them with available results.

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