185 research outputs found
The Schwinger-Dyson equation on Pomeron loop summation and renormalization
The solution to the Schwinger-Dyson equation that describes the summation
over Pomeron loop diagrams is derived. The solution is a closed expression
which splits into two parts. The first leads directly to the renormalization of
the BFKL Pomeron, and the second contribution is equivalent to non interacting
Pomerons with renormalized vertices. Thus a closed expression is derived for
the sum over Pomeron loop diagrams in the perturbative QCD approach, which
preserves unitarity.Comment: 18 pages, 8 Figure
Selection rules at the quark-antiquark vertex of the QCD Pomeron
We derive the full analytic expression for the QCD eikonal coupling of a
quark-antiquark state to the exchanged gluon-gluon state in the BFKL formalism.
The formula is valid for all conformal spin configurations of the
quark-antiquark and gluon-gluon states. In particular, a new selection rule on
conformal spins characterizes the non-dominant BFKL components with intercept
below the Pomeron in the conformal-invariant framework.Comment: 12 pages, latex with tcilatex, no figur
Revisiting the phenomenology on the QCD color dipole picture
Using the QCD dipole picture of the hard BFKL Pomeron, we perform a 3
parameter fit analysis of the recent inclusive structure function experimental
measurements at small- and intermediate . As a byproduct, the
longitudinal structure function and the gluon distribution are predicted
without further adjustments. The data description is quite reasonable, being
timely a further study using resummed NLO BFKL kernels along the lines of
recent theoretical developments.Comment: Contribution to the ``International Workshop on Diffraction in
High-Energy Physics'' (DIFFRACTION 2004), Cala Gonone (Sardinia, Italy),
18-23 September 2004; 3 pages, LaTeX fil
On Certain Two Dimensional Integrals that Appear In Conformal Field Theory
In a first part, we generalize a theorem for an holomorphic
anti-holomorphic integrand, in the case of 2 dimensional Fourier transform. In
the second part, we derive p-uple conformal integrals the integrand of which
are linear combination of holomorphic times holomorphic generalized
hypergeometric functions. The specific case is relevant to determine the
triple Pomeron vertex in QCD.Comment: latex txt.tex, 3 files, 39 pages [SPhT-T00/034], submitted to Comm.
Math. Phy
Deep-Inelastic Onium Scattering
Using the colour dipole approach of the QCD perturbative (BFKL) Pomeron
exchange in onium-onium scattering, we compute the cross section for small but
hierarchically different onium sizes. A specific term dependent on the
size-ratio is generated. In deep inelastic onium scattering it appears as a
scaling violation contribution to the quark structure function near the BFKL
singularity. We find that the extension of the formalism for deep inelastic
onium scattering to the proton structure function provides a remarkably good
3-parameter fit to HERA data at small x with a simple physical interpretation
in terms of the dipole formulation.Comment: 10 pages, 2 Postscript figure
total cross-section in the dipole picture of BFKL dynamics
The total cross-section is derived in the Leading Order
QCD dipole picture of BFKL dynamics, and compared with the one from 2-gluon
exchange. The Double Leading Logarithm approximation of the DGLAP cross-section
is found to be small in the phase space studied. Cross sections are calculated
for realistic data samples at the collider LEP and a future high
energy linear collider. Next to Leading order corrections to the BFKL evolution
have been determined phenomenologically, and are found to give very large
corrections to the BFKL cross-section, leading to a reduced sensitivity for
observing BFKL.Comment: 24 pages, 4 figure
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