125 research outputs found
BFKL at next-to-leading order
This is a summary of the contributions on the next-to-leading order
corrections to the BFKL equation which were presented to the `Small-x and
Diffraction' working group at the 1998 Durham Workshop on HERA Physics.Comment: 6 pages, 2 figure
Baxter Equation for the QCD Odderon
The Hamiltonian derived by Bartels, Kwiecinski and Praszalowicz for the study
of high-energy QCD in the generalized logarithmic approximation was found to
correspond to the Hamiltonian of an integrable spin chain. We study the
odderon Hamiltonian corresponding to three sites by means of the Bethe Ansatz
approach. We rewrite the Baxter equation, and consequently the Bethe Ansatz
equations, as a linear triangular system. We derive a new expression for the
eigenvectors and the eigenvalues, and discuss the quantization of the conserved
quantities.Comment: 14 pages, latex file, one figur
Resummation of double logarithms in electroweak high energy processes
At future linear collider experiments in the TeV range, Sudakov
double logarithms originating from massive boson exchange can lead to
significant corrections to the cross sections of the observable processes.
These effects are important for the high precision objectives of the Next
Linear Collider. We use the infrared evolution equation, based on a gauge
invariant dispersive method, to obtain double logarithmic asymptotics of
scattering amplitudes and discuss how it can be applied, in the case of broken
gauge symmetry, to the Standard Model of electroweak processes. We discuss the
double logarithmic effects to both non-radiative processes and to processes
accompanied by soft gauge boson emission. In all cases the Sudakov double
logarithms are found to exponentiate. We also discuss double logarithmic
effects of a non-Sudakov type which appear in Regge-like processes.Comment: 26 pages, 3 figures, Latex2
Near-integrability and confinement for high-energy hadron-hadron collisions
We investigate an effective Hamiltonian for QCD at large s, in which
longitudinal gauge degrees of freedom are suppressed, but not eliminated. In an
axial gauge the effective field theory is a set of coupled (1+1)-dimensional
principal-chiral models, which are completely integrable. The confinement
problem is solvable in this context, and we find the longitudinal and
transverse string tensions with techniques already used for a similar
Hamiltonian in (2+1)-dimensions. We find some a posteriori justification for
the effective Hamiltonian as an eikonal approximation. Hadrons in this
approximation consist of partons, which are quarks and soliton-like excitations
of the sigma models. Diffractive hadron-hadron scattering appears primarily due
to exchange of longitudinal flux between partons.Comment: Typographical errors corrected, language improved, reference adde
Exclusive diffractive production of real photons and vector mesons in a factorized Regge-pole model with non-linear Pomeron trajectory
Exclusive diffractive production of real photons and vector mesons in ep
collisions has been studied at HERA in a wide kinematic range. Here we present
and discuss a Regge-type model of real photon production (Deeply Virtual
Compton Scattering), as well as production of vector mesons (VMP) treated on
the same footing by using an extension of a factorized Regge-pole model
proposed earlier. The model has been fitted to the HERA data. Despite the very
small number of the free parameters, the model gives a satisfactory description
of the experimental data, both for the total cross section as a function of the
photon virtuality Q2 or the energy W in the center of mass of the gamma\star-p
system, and the differential cross sections as a function of the squared
four-momentum transfer t with fixed Q2 and W.Comment: 34 pages, 82 figures accepted by Physical Review
Effective Regge QCD
A new framework for a high energy limit of quantum gauge field theories is
introduced. Its potency is illustrated on a new derivation of the reggeization
of the gluon.Comment: Latex, 9 pages + 2 figures as PS-file, extended version, to appear in
Phys. Rev. Let
Disperse composition of dust in hydro-metallurgical production of copper
The article describes the main technological processes of pyroand hydrometallurgy of copper. Air sampling of the working area was carried out in accordance with PNDF 13: 2: 3.71-11. A brief comparative characteristic of the dispersed dust composition is given.В статье рассмотрены основные технологические процессы пиро- и гидрометаллургии меди. Проведен отбор проб воздуха рабочей зоны в соответствии с ПНДФ 13:2:3.71-11. Дана краткая сравнительная характеристика дисперсного состава пыли
Solution of the Odderon Problem
The intercept of the odderon trajectory is derived, by finding the spectrum
of the second integral of motion of the three reggeon system in high energy
QCD. When combined with earlier solution of the appropriate Baxter equation,
this leads to the determination of the low lying states of that system. In
particular, the energy of the lowest state gives the intercept of the odderon
alpha_O(0)=1-0.2472 alpha_s N_c/pi.Comment: 11 pages, 2 Postscript figure
Infrared safety of impact factors for colourless particle interactions
We demonstrate, to next-to-leading order accuracy, the cancellation of the
infrared singularities in the impact factors which arise in the QCD description
of high energy processes A + B -> A' + B' of colourless particles. We study the
example where A is a virtual photon in detail, but show that the result is true
in general.Comment: 31 pages latex including 10 figure
Virtual Next-to-Leading Corrections to the Impact Factors in the High-Energy Limit
We compute the virtual next-to-leading corrections to the impact factors or
off-shell coefficient functions in the high-energy limit. When combined with
the known real corrections, these results will provide the complete NLO
corrections to the impact factors, which are necessary to use the BFKL
resummation at NLL for jet production at both lepton-hadron and hadron-hadron
colliders.Comment: LaTeX, 23 page
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