8,732 research outputs found
Pomeron Vertices in Perturbative QCD in Diffractive Scattering
We analyse the momentum space triple Pomeron vertex in perturbative QCD. In
addition to the standard form of this vertex which is used in the context of
total cross-sections at high energies and in the QCD reggeon field theory,
there exists an alternative form which has to be used in the study of high-mass
diffraction. We review and analyse the relation between these two versions. We
discuss some implications for the BK-equation. In the second part of our paper
we extend this analysis to the Pomeron-Odderon-Odderon vertex.Comment: 23 pages, 5 figures, Late
AGK Cutting Rules and Multiple Scattering in Hadronic Collisions
We discuss the AGK rules for the exchange of an arbitrary number of reggeized
gluons in perturbative QCD in the high energy limit. Results include the
cancellation of corrections to single jet and double jet inclusive cross
sections, both for hard and soft rescattering contributions.Comment: 31 pages, latex, 20 figure
Generalized Bootstrap Equations and possible implications for the NLO Odderon
We formulate and discuss generalized bootstrap equations in nonabelian gauge
theories. They are shown to hold in the leading logarithmic approximation.
Since their validity is related to the self-consistency of the Steinmann
relations for inelastic production amplitudes they can be expected to be valid
also in NLO. Specializing to the N=4 SYM, we show that the validity in NLO of
these generalized bootstrap equations allows to find the NLO Odderon solution
with intercept exactly at one, a result which is valid also for the planar
limit of QCD.Comment: 20 pages, latex, 11 figures, Comments added, To appear on EPJ
QCD Corrections to Electroweak Vector Boson Scattering at Small Scattering Angles
We investigate the role of a certain class of QCD corrections to electroweak
vector boson scattering at small scattering angles and large energies. These
are present since, from the perturbative analysis, the vector bosons may
dissociate into quark-antiquark pairs giving rise to colour dipoles interacting
through gluon exchanges. After the computation of the vector boson impact
factors, we present expressions for the lowest order QCD scattering amplitude
and for the leading logarithmic BFKL amplitude. Particularly we discuss
numerical results for the process . The QCD corrections to
the cross section resulting from the interference with the electroweak ones are
estimated and compared with the leading pure electroweak part. Corrections
resulting from the leading log BFKL amplitude are of the order of few percent
already at the TeV energy range.Comment: 21 pages,9 figures, discussion on the helicity-flip impact factors
added, typos correcte
Multiple interactions and AGK rules in pQCD
We review some aspects of multiple interactions in High Energy QCD; we
discuss in particular AGK rules and present some results concerning multiple
interactions in the context of jet production.Comment: Talk given by MS at 12th International Conference on Elastic and
Diffractive Scattering: Forward Physics and QCD, Hamburg, DESY, Germany,
21-25 May 2007. 7pp. Minor change
The NLO Jet Vertex for Mueller-Navelet and Forward Jets: the Quark Part
We calculate the next-to-leading corrections to the jet vertex which is
relevant for the Mueller-Navelet-jets production in p-pbar collisions and for
the forward jet cross section in e-p collisions. In this first part we present
the results of the vertex for an incoming quark. Particular emphasis is given
to the separation of the collinear divergent part and the central region of the
produced gluon.Comment: 28 pages, 8 eps figure
The NLO Jet Vertex for Mueller-Navelet and Forward Jets: the Gluon Part
In this paper we complete our calculation of the NLO jet vertex which is part
of the cross section formulae for the production of Mueller Navelet jets at
hadron hadron colliders and of forward jets in deep inelastic electron proton
scattering.Comment: 16 pages, latex, epj style, 6 eps figure
A momentum Space Analysis of the Triple Pomeron Vertex in pQCD
We study properties of the momentum space Triple Pomeron Vertex in
perturbative QCD. Particular attention is given to the collinear limit where
transverse momenta on one side of the vertex are much larger than on the other
side. We also comment on the kernels in nonlinear evolution equations.Comment: Minor misprints corrected. To be published in EPJ
On the Triple Pomeron Vertex in Perturbative QCD
We estimate the size of the triple Pomeron vertex in perturbative QCD and
compare with the phenomenological value extracted from Regge fits to
experimental data. For simplicity, the results of the QCD analysis are taken in
the large-N_c limit. We find that the perturbative triple Pomeron coupling is
of the same order of magnitude as the observed one. We also estimate the size
of the Pomeron self energy and its contribution to the renormalization of the
Pomeron intercept. The effect is very small, in agreement with previous
nonperturbative estimates.Comment: 24 pages, 4 figure
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