276 research outputs found
The Hilbert-Space Structure of Non-Hermitian Theories with Real Spectra
We investigate the quantum-mechanical interpretation of models with
non-Hermitian Hamiltonians and real spectra. After describing a general
framework to reformulate such models in terms of Hermitian Hamiltonians defined
on the Hilbert space , we discuss the significance of the
algebra of physical observables.Comment: 5 pages, uses iopart.cls. Talk given by R. Kretschmer at the 1st
International Workshop on Pseudo-Hermitian Hamiltonians in Quantum Physics,
Prague, Czech Republic, June 16-17, 2003. To appear in the proceeding
Next-to-leading gluonic reggeons in the high-energy effective action
We study the next-to-leading gluon exchange in the high-energy scattering
that contributes to the amplitude to order up to logarithmic corrections.
Similar to the leading gluon exchange these contribution can be described in
terms of reggeon exchanges. There are several gluonic reggeons at the
next-to-leading level. Some of them transfer parity or gauge group
representation different from the leading gluonic reggeon. Unlike the leading
one they are sensitive to the helicity and transverse momenta of the scattering
partons. We extend the high-energy effective action and derive from the action
of gluodynamics the terms describing the next-to-leading reggeons and their
interaction in the multi-Regge approximation.Comment: 31 pages in LATEX, 4 eps figures, references adde
Diffractive meson production from virtual photons with odd charge-parity exchange
We calculate the cross section of diffractive charge-parity C=+1 neutral
meson production in virtual photon proton collision at high energies. Due to
the opposite C-parities of photon and meson M (M = eta_C, pi^0, a_2) this
process probes the t-channel C=-1 odderon exchange which is described here as
noninteracting three-gluon exchange. Estimates for the cross section of the
inelastic diffractive process gamma^* p -> eta_C X_p are presented. The total
cross section of diffractive \eta_C meson photoproduction is found to be 47 pb.
The cross sections for the diffractive production of light mesons (pi^0, a_2)
in \gamma^* p collisions are of the same order if the photon virtuality Q^2 is
m^2_C.Comment: LaTeX, 19 pages, 8 ps-figs, epsfi
Hard Pomeron in exclusive meson production at ILC
We calculate the exclusive process gamma* gamma* ->rho rho at high energy.
The Born order estimate and the leading (LLA) and next to leading order (NLLA)
BFKL resummation effects show the feasibility of experimental detection in a
quite large range of Q2 values at future high energy e+e- linear colliders.Comment: 4 pages, Presented at Photon2005, International Conference on the
Structure and Interactions of the Photon, Warsaw 31.08-04.09.2005, by Samuel
Wallo
Revealing transversity GPDs through the photoproduction of a photon and a meson
Photoproduction of a pair of particles with large invariant mass is a natural
extension of collinear QCD factorization theorems which have been much studied
for deeply virtual Compton scattering and deeply virtual meson production. We
discuss the production of a photon and a meson, where the wide angle Compton
scattering on a meson subprocess factorizes from generalized parton
distribution. We calculate at dominant twist and leading order in ,
the production cross-section of a transversely polarized meson which is
sensitive to chiral-odd GPDs, and show that it may be measurable in near future
JLab experiments.Comment: 6 pages, 3 figures. Contribution to the proceedings of the 6th
International Conference on Physics Opportunities at an Electron-Ion Collider
(POETIC6), September 7-11, 2015, Palaiseau, France. The numerical plot
(fig.3) has been corrected. arXiv admin note: text overlap with
arXiv:1511.0437
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