676 research outputs found
Total Cross-sections and Bloch-Nordsieck Gluon Resummation
The physics underlying the fall and eventual rise in various total
cross-sections at high energies has been investigated over a decade using a
model based on the Bloch-Nordsieck resummation in QCD. Here a brief review of
our latest results is presented and comparison made with experimental data on
, and total cross-sections.Comment: Presented by G. Pancheri at ISMD04, Sonoma State University. Under
publication in Acta Physica Polonica. LaTeX format, 10 *.eps files, 7 page
Total cross-section at LHC from minijets and soft gluon resummation in the infrared region
A model for total cross-sections incorporating QCD jet cross-sections and
soft gluon resummation is described and compared with present data on and
cross-sections. Predictions for LHC are presented for different
parameter sets. It is shown that they differ according to the small x-behaviour
of available parton density functions.Comment: 10 pages, 3 figures, uses appolb.cls, LaTeX. Talk presented by G.
Pancheri at the EURIDICE Final Meeting, August 24-27th, 2006, Kazimierz,
Polan
Total Cross-sections at very high energies: from protons to photons
A model for both proton and photon total cross-sections is presented and
compared with data. The model is based on the eikonal representation, with QCD
mini-jets to drive the rise and soft gluon kt-resummation into the Infrared
region to tame the excessive rise due to low-x perturbative gluons. We discuss
the effects of a singular but integrable expression for the Infrared gluon
spectrum on the high energy behaviour of the total cross-section expected in
this model.Comment: 13 pages, 4 figures, Tenth Workshop on Non-Perturbative Quantum
Chromodynamics at l'Institut Astrophysique de Paris, June 8-12, 200
Soft Gluons and the Energy Dependence of Total Cross-Sections
We discuss the high energy behaviour of total cross-sections for protons and
photons, in a QCD based framework with particular emphasis on the role played
by soft gluonsComment: 13 pages, 10 figures, Presented by G. Pancheri at the International
Workshop on QCD, Martina Franca, Italy, June 16-20,2001. To appear in the
proceeding
Total cross sections and soft gluon resummation
We discuss a model for total hadronic and photonic cross-sections which
includes hard parton-parton scattering to drive the rise and soft gluon
resummation to tame it. Unitarity is ensured by embedding the cross-section in
the eikonal formalism. Predictions for LHC and ILC are presented.Comment: 9 pages, 2 figures, Presented at PLC2005, Kazimierz, September 2005,
requires appolb.cl
QCD Mini-jet contribution to the total cross section
We present the predictions of a model for proton-proton total cross-section
at LHC. It takes into account both hard partonic processes and soft gluon
emission effects to describe the proper high energy behavior and to respect the
Froissart bound.Comment: 7 pages, 3 figures, presented at MPI08, Perugia, October 27-31, 200
Mini-jet Total Cross-sections and Overlap Functions through Bloch-Nordsieck Summation
Predictions for total inelastic cross-sections for photon induced processes
are discussed in the context of the QCD-inspired minijet model. Large
theoretical uncertainties exist, some of them related to the parton
distributions of hadrons in impact parameter space. A model for such
distribution is presented, based on soft gluon summation. This model
incorporates (the salient features of distributions obtained from) the
intrinsic transverse momentum behaviour of hadrons. Under the assumption that
the intrinsic behaviour is dominated by soft gluon emission stimulated by the
scattering process, the b-spectrum becomes softer and softer as the scattering
energy increases. In minijet models for the inclusive cross-sections, this will
counter the increase from .Comment: 11 pages, two postscript figures, latex, uses epsfig.sty, a4wide.sty
full postscript file of the paper is available at
http://hpteor.lnf.infn.it/pancheri/starelesna.p
Zero momentum gluons and the total pp and pbarp cross-sections
We describe a QCD motivated model for total cross-sections which uses the
eikonal representation and incorporates QCD mini-jets to drive the rise with
energy of the cross-section, while the impact parameter distribution is
obtained through the Fourier transform of the transverse momentum distribution
of soft gluons emitted in the parton-parton interactions giving rise to
mini-jets in the final state. A singular but integral expression for the
running coupling constant in the infrared region is part of this model.Comment: 4 pages, 1 figure, uses slac_one.rtx, 34th ICHEP Conference,
Philadelphia 200
Total Cross-Sections : Cross-Talk between HERA, LHC and LC
We discuss the need to compare total cross-section measurements at LHC and
HERA with each other and with available models in order to obtain a more
precise prediction of the total hadronic cross-section at the future Linear
Collider, thus leading to a better estimate of the hadronic background.Comment: 5 pages, three figures, Talk presented by G. Pancheri at the
International Linear Collider Workshop, Paris, April, 200
Hierarchical hybrid control: A case study
A case study of the difficulties encountered in the design of hierarchical, hybrid control systems is presented. As our example we use the Intelligent Vehicle Highway System (IVHS) architecture proposed for vehicle platooning, a system that involves both continuous state and discrete event controllers. We point out that even though conventional analysis tools suggest that the proposed design should fulfill certain performance requirements, simulation results show that it does not. We consider this as an indication that the conventional tools currently in use for the design and verification of control systems may be inadequate for the design of hierarchical controllers for hybrid systems. The analysis also indicates certain shortcomings of the current IVHS design. We propose solutions to fix these problems
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