498 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
A simple recipe to detect possible C-Odd effects in high energy and
We provide a theorem to suggest that  data may already be sufficient to
detect possible asymptotic C-odd (Odderon) contributions. This can be done by
comparing  and   observables such as total cross sections,
forward angular distributions and ratios of real to imaginary forward
amplitudes for which well defined model independent correlations {must} exist
which could already show up at RHIC energy but definitely at LHC energies.Comment: 10 pages in TeX, no figur
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
The Two-Component Non-Perturbative Pomeron and the G-Universality
In this communication we present a generalization of the Donnachie-Landshoff
model inspired by the recent discovery of a 2-component Pomeron in LLA-QCD by
Bartels, Lipatov and Vacca. In particular, we explore a new property, not
present in the usual Regge theory - the G-Universality - which signifies the
independence of one of the Pomeron components on the nature of the initial and
final hadrons. The best description of all the forward hadron-hadron, gamma-
gamma and gamma-proton data is obtained when G-universailty is imposed.
Moreover, the maximal (ln)**2 behaviour of the hadron amplitude, first
established by Heisenberg, is clearly favoured by the data.Comment: 5 pages, 2 tables, talk at the International Workshop on Diffraction
  in High-Energy Physics "Diffraction 2000", Cetraro, Italy, September 2-7,
  200
Nucleon Structure and High Energy Scattering
If the pomeron is generated by a two gluon exchange there is no a priori
reason for a drastic suppression of three gluon exchange with negative parity
and charge parity. This would lead to an unacceptably large difference between
 and  scattering. It is shown that a natural suppression of
the ==--1 contribution to high energy scattering is given by a cluster
structure of the nucleon.Comment: 10 pages, epsf.sty and a4wide.sty, 8 eps figs included complete
  PS-file (with all figs) available at:
  http://www.thphys.uni-heidelberg.de/~rueter
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 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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