90 research outputs found
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
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
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
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 a study of many possible analytic
parametrisations and invoke the current hadronic dataset at t=0. The
uncertainties on total cross sections, including the systematic theoretical
errors, reach 1% at RHIC, 3% at the Tevatron, and 10% at the LHC, whereas those
on the rho parameter are respectively 10%, 17%, and 26%.Comment: 11 pages, 2 figures, LaTeX, presented at the Second International
"Cetraro" Workshop & NATO Advanced Research Workshop "Diffraction 2002",
Alushta, Crimea, Ukraine, August 31 - September 6, 200
Heisenberg's Universal (lns)**2 Increase of Total Cross Sections
The (lns)**2 behaviour of total cross-sections, first obtained by Heisenberg
50 years ago, receives now increased interest both on phenomenological and
theoretical levels. In this paper we present a modification of the Heisenberg's
model in connection with the presence of glueballs and we show that it leads to
a realistic description of all existing hadron total cross-section data.Comment: 6 pages, 3 figure
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
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
The Goldberger-Miyazawa-Oehme sum rule revisited
The Goldberger-Miyazawa-Oehme sum rule is used to extract the pion-nucleon
coupling constant from experimental N information. Chiral perturbation
theory is exploited in relating the pionic hydrogen s-wave level shift and
width results to the appropriate scattering lengths. The deduced value for the
coupling is , where the largest source of uncertainty is
the determination of the s-wave scattering length from the atomic
level shift measurement.Comment: 4 pages, 1 figure. v2: Revised the second last paragraph of 5th
section and clarified the electromagnetic corrections (Tromborg vs.
PT). Also removed the KH80 slope from the fig.
Symmetry Properties of the Effective Action for High-Energy Scattering in QCD
We study the effective action describing high-energy scattering processes in
the multi-Regge limit of QCD, which should provide the starting point for a new
attempt to overcome the limitations of the leading logarithmic and the eikonal
approximations. The action can be obtained via simple graphical rules or by
integrating in the QCD functional integral over momentum modes of gluon and
quark fields that do not appear explicitely as scattering or exchanged
particles in the considered processes. The supersymmetry is used to obtain the
terms in the action involving quarks fields from the pure gluonic ones. We
observe a Weizs\"acker - Williams type relations between terms describing
scattering and production of particles.Comment: 37 pages LATEX, 1 Table and 7 figures using package FEYNMA
Direct solution of the hard pomeron problem for arbitrary conformal weight
A new method is applied to solve the Baxter equation for the one dimensional
system of noncompact spins. Dynamics of such an ensemble is equivalent to that
of a set of reggeized gluons exchanged in the high energy limit of QCD
amplitudes. The technique offers more insight into the old calculation of the
intercept of hard Pomeron, and provides new results in the odderon channel.Comment: Contribution to the ICHEP96 Conference, July 1996, Warsaw, Poland.
LaTeX, 4 pages, 3 epsf figures, includes modified stwol.sty file. Some
references were revise
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