Related papers: t-channel unitarity and photon cross sections
After a brief look at the well-known standard approaches to determine the angle gamma of the unitarity triangle, we focus on two kinds of strategies, employing $B\to\pi K$ modes, and U-spin-related B decays. Interesting "puzzles", which may…
We develop a model for describing excited mesons decay into three mesons. The properties of the excited mesons can be extracted with this model. The model maintains the three-body unitarity that has been missed in previous data analyses…
An exposition is made of recent developments using techniques of unitary chiral perturbation theory, $U \chi P T$, which allows one to extend predictions using chiral Lagrangians to higher energies than ordinary chiral perturbation theory,…
We analyze single particle coherence and interference in the presence of particle loss and derive an inequality that relates the preservation of coherence, the creation of superposition with the vacuum, and the degree of particle loss. We…
After a short discussion on the definition of isolated-photon cross sections in perturbative QCD, I present phenomenological predictions relevant for polarized hadron-hadron collisions in the RHIC energy range. The possibility of measuring…
This report discusses some results on differential cross sections for high energy and small momentum transfer elastic hadron-hadron scattering in QCD, using a functional integral approach. In particulary a matrix cumulant expansion for the…
A derivation of the t-J model of a highly-correlated solid is given starting from the general many-electron Hamiltonian with account of the non-orthogonality of atomic wave functions. Asymmetry of the Hubbard subbands (i.e. of ``electron''…
In the theoretical analysis of high-energy elastic nucleon scattering one starts commonly from the description based on the validity of optical theorem, which allows to derive the value of total cross section directly from the…
A search for single top quark production is performed in e^\pm p collisions at HERA. The search exploits data corresponding to an integrated luminosity of 118.3 pb^-1. A model for the anomalous production of top quarks in a flavour changing…
We describe new QCD fits to diffractive cross sections measured at HERA and we use the parton densities derived from these fits to predict the shape of the dijet mass fraction in double Pomeron exchange at the Tevatron. We discuss the…
A selection of theoretical and experimental results are presented in the broader context of understanding QCD and its relation to photon physics. A phenomenological analysis of HERA data to constrain the gluon content of the proton and…
Data from HERA, LEP and the Tevatron, as well as from low energy experiments are used to constrain the Yukawa couplings for scalar and vector leptoquarks in the Buchmuller-Ruckl-Wyler effective model. In the limit of very high leptoquark…
An analysis of all experimental data of 50's - 90's on elastic gamma-p scattering at photon energies below 150 MeV (10 experimental works) is performed in order to determine the electric (alpha_p) and magnetic (beta_p) polarizabilities of…
The LHC is now exploring the 1-3 TeV scale where resonances of the Electroweak Symmetry Breaking Sector might exist. If so, Unitarized Effective Theory can be used to describe the data with all the constraints of unitarity, causality and…
New results reported at the Moriond-QCD 2003 conference from the experiments ALEPH, DELPHI, L3, and OPAL on the structure of the photon as well as heavy quark production in gammagamma collisions are presented. The hadronic structure of the…
A unified approach to total cross-sections, based on the QCD contribution to the rise with energy, is presented for the processes $pp$, $p{\bar p}$, $\gamma p, \gamma \gamma, e^+e^- \to hadrons$. For proton processes, a discussion of the…
Longitudinal polarization of the HERA electron beam allows the study of spatial asymmetries in the final state of single inclusive hadron production in $\vec{e}p$-collisions. We estimate the size of a particular production asymmetry which…
We use an almost model-independent analytical parameterization for $pp$ and $\bar{p}p$ elastic scattering data to analyze the eikonal, profile, and inelastic overlap functions in the impact parameter space. Error propagation in the fit…
The parton distribution functions (PDFs) are a non-negotiable input to almost all theory predictions at hadron colliders. In this talk, I introduce PDF determination by global analysis and discuss selected topics concerning recent relevant…
The problems linked with the extraction of the basic parameters of the hadron elastic scattering amplitude at the LHC are explored. It is shown that one should take into account the saturation regime which will lead to new effects at the…