186 research outputs found
Direct Calculations of the Odderon Intercept in the Perturbative QCD
The odderon intercept is calculated directly, from its expression via an
average energy of the odderon Hamiltonian, using both trial wave functions in
the variational approach and the wave function recently constructed by
R.A.Janik and J.Wosiek.
The results confirm their reported value for the energy. The odderon
intercept is calculated directly, from its expression via an average energy of
the odderon Hamiltonian, using both trial wave functions in the variational
approach and the wave function recently constructed by R.A.Janik and
J.Wosiek.The results confirm their reported value for the energy. Variational
calculations give energies some 30% higher. However they also predict the
odderon intercept to be quite close to unity. In fact, for realistic values of
, the intercept calculated variationally is at most 2% lower than the
exact one: 0.94 instead of 0.96. It is also found that the solution for
does not belong to the odderon spectrum. The diffusion parameter is found to be
of the order 0.6.Comment: 20 page
Calculation of the real part of the nuclear amplitude at high s and small t from the Coulomb amplitude
A new method for the determination of the real part of the elastic scattering
amplitude is examined for high energy proton-proton at small momentum transfer.
This method allows us to decrease the number of model assumptions, to obtain
the real part in a narrow region of momentum transfer and to test different
models. The possible non-exponential behavior of the real part was found on the
base of the analysis of the ISR experimental data.Comment: 5 pages, 3 figures, Talk on XIth International Conference on Elastic
and Diffractive Scatterin
A Possible Two-Component Structure of the Non-Perturbative Pomeron
We propose a QCD-inspired two-component Pomeron form which gives an excellent description of the proton-proton, pi-proton, kaon-proton, gamma-proton and gamma-gamma total cross sections. Our fit has a better CHI2/dof for a smaller number of parameters as compared with the PDG fit. Our 2-Pomeron form is fully compatible with weak Regge exchange-degeneracy, universality, Regge factorization and the generalized vector dominance model
How can the Odderon be detected at RHIC and LHC
The Odderon remains an elusive object, 33 years after its invention. The
Odderon is now a fundamental object in QCD and CGC and it has to be found
experimentally if QCD and CGC are right. In the present paper, we show how to
find it at RHIC and LHC. The most spectacular signature of the Odderon is the
predicted difference between the differential cross-sections for proton-proton
and antiproton-proton at high s and moderate t. The experiment can be done by
using the STAR detector at RHIC and by combining these future data with the
already present UA4/2 data. The Odderon could also be found by ATLAS
exeperiment at LHC by performing a high-precision measurement of the real part
of the hadron elastic scattering amplitude at small t.Comment: 14 pages, 16 figures, two typographical errors corrected and
acknowledgments adde
Analytic Amplitude Models for Forward Scattering
We report on fits of a large class of analytic amplitude models for forward
scattering against the comprehensive data for all available reactions. To
differentiate the goodness of the fits of many possible parametrizations to a
large sample of data, we developed and used a set of quantitative indicators
measuring statistical quality of the fits over and beyond the typical criterion
of the . These indicators favor models with a universal
Pomeron term, which enables one to extend the fit down to GeV.Comment: 13 pages, COMPETE Collaboration, talk presented at the 9th
International Conference (Blois Workshop) on Elastic and Diffractive
Scatterin
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
Analytic parametrizations of the non-perturbative Pomeron and QCD-inspired models
We consider several classes of analytic parametrizations of hadronic
scattering amplitudes, and compare their predictions to all available forward
data (proton- proton, antiproton-proton, pion-proton, kaon-proton,
photon-proton, photon- photon, sigma-proton). Although these parametrizations
are very close for energy larger than 9 GeV, it turns out that they differ
markedly at low energy, where a universal Pomeron term ~(ln s)**2 enables one
to extend the fit down to 4 GeV.Comment: 11 pages, 2 tables, Presented at the 9th Blois Workshop on Elastic
and Diffractive Scattering, Pruhonice, Czech Republic, 9-15 June 200
Benchmarks for the Forward Observables at RHIC, the Tevatron-run II and the LHC
We present predictions on the total cross sections and on the ratio of the
real part to the imaginary part of the elastic amplitude (rho parameter) for
present and future pp and pbar p colliders, and on total cross sections for
gamma p -> hadrons at cosmic-ray energies and for gamma gamma-> hadrons up to
sqrt{s}=1 TeV. These predictions are based on an extensive study of possible
analytic parametrisations invoking the biggest hadronic dataset available at
t=0. The uncertainties on total cross sections, including the systematic errors
due to contradictory data points from FNAL, can reach 1.9% at RHIC, 3.1% at the
Tevatron, and 4.8% at the LHC, whereas those on the rho parameter are
respectively 5.4%, 5.2%, and 5.4%.Comment: 11 pages, 2 figures, 4 tables, RevTeX
New measures of the quality and of the reliability of fits applied to forward hadronic data at t=0
We develop five new statistical measures of the quality of fits, which we
combine with the usual confidence level to determine the models which fit best
all available data for total cross sections and for the real part of the
forward hadronic amplitude.Comment: 7 pages, presented by J.R. Cudell on behalf of the COMPETE
collaboration at the 6th workshop on non-perturbative QCD, American
University of Paris, 5-9 June 200
Analytic Amplitudes for Hadronic Forward Scattering : COMPETE Update
We consider several classes of analytic parametrizations of hadronic
scattering amplitudes, and compare their predictions to all available forward
data in hadron-hadron, gamma-p and gamma-gamma reactions. Although these
parametrizations are very close for SQRTs larger than 9 GeV, it turns out that
they differ markedly at low energy, where a universal Pomeron term like ln**2 s
enables one to extend the fit down to SQRTs equal to 4 GeV. We present
predictions on the total cross sections and on the ratio of the real part to
the imaginary part of the elastic amplitude (RHO parameter) for present and
future pp and antipp colliders, and on total cross sections for gamma-p into
hadrons at cosmic-ray energies and for gamma-gamma into hadrons up to SQRTs
equal to 1 TeV.Comment: 3 pages, 3 tables. To be published in the Proceedings of the 31st
International Conference on High Energy Physics (ICHEP 2002), Amsterdam, The
Netherlands, 24-31 July 200
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