58 research outputs found
The growth with energy of exclusive and photo-production cross-sections and BFKL evolution
We investigate whether NLO BFKL evolution is capable to describe the energy
dependence of the exclusive photo-production cross-section of vector mesons
and on protons. Our description is based on available NLO
BFKL fits of the proton impact factor in inclusive DIS, which allow us to
construct the necessary scattering amplitude at zero momentum transfer .
Assuming an exponential drop-off with , this result allows us to calculate
the exclusive photoproduction cross-section. Comparing our results with both
HERA data (measured by H1 and ZEUS collaborations in collision) and LHC
data (measured by ALICE, CMS and LHCb collaborations in ultra-peripheral
and collision) we find that our framework provides a very good
description of the energy dependence of the and
photoproduction cross-section, providing therefore further evidence for BFKL
evolution at the LHC. The available fits of the proton impact factor require on
the other hand an adjustment in the overall normalization.Comment: 4 pages, 4 figures; Proceedings of the International Workshop on
Diffraction in High-Energy Physics (DIFFRACTION 2016), September 2 - 8, 2016,
Acireale (Italy
The effective action and the triple Pomeron vertex
We study integrations over light-cone momenta in the gauge invariant
effective action of high energy QCD. A regularization mechanism which allows
for the evaluation of the longitudinal integrations is presented. After a
rederivation of the reggeized gluon and the BFKL-equation from the effective
action, we study the 1-3 and 2-4 reggeized gluon transition vertex of QCD
Reggeon field theory and discuss their connection with the usual triple Pomeron
vertex of perturbative QCD.Comment: Talk given at the 3rd International Hadron Structure '09 Conference,
Tatranska Strba, Slovakia, 30 Aug - 3 Sep 2009; 4 pages, 16 figure
Extension of the Color Glass Condensate Approach to Diffractive Reactions
We present an evolution equation for the Bjorken x dependence of diffractive
dissociation on hadrons and nuclei at high energies. We extend the formulation
of Kovchegov and Levin by relaxing the factorization assumption used there. The
formulation is based on a technique used by Weigert to describe interjet energy
flow. The method can be naturally extended to other exclusive observables
High Energy Behavior of a Six-Point R-Current Correlator in N=4 Supersymmetric Yang-Mills Theory
We study the high energy limit of a six-point R-current correlator in N=4
supersymmetric Yang-Mills theory for finite N_c. We make use of the framework
of perturbative resummation of large logarithms of the energy. More
specifically, we apply the (extended) generalized leading logarithmic
approximation. We find that the same conformally invariant two-to-four gluon
vertex occurs as in non-supersymmetric Yang-Mills theory. As a new feature we
find a direct coupling of the four-gluon t-channel state to the R-current
impact factor.Comment: 47 page
NLO corrections to the gluon induced forward jet vertex from the high energy effective action
We determine both real and virtual next-to-leading order corrections to the
gluon induced forward jet vertex, from the high energy effective action
proposed by Lipatov. For these calculations we employ the same regularization
and subtraction formalism developed in our previous work on the quark-initiated
vertex. We find agreement with previous results in the literature.Comment: 16 page
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