Trans-Eurasian Land Transport Corridors: Assessment of Prospects and Barriers

This study is part of the “Challenges and Opportunities of Economic Integration within a Wider European and Eurasian Space” project, an ambitious undertaking seeking to scope the complex issues and potentials for economic cooperation between the European Union (EU) and the Eurasian Economic Union (EAEU), as well as with third-party countries of the vast Eurasian landmass. It is based on the intense research going on in over 25 countries, including Member-States of both the EU and the EAEU, the United States, China, Japan, Turkey and Ukraine, and on the results of seven international project workshops held at IIASA from June 2013 to April 2016, which discussed and synthesized these analyses. The project workshops were attended by renowned academics and high-level policymakers, including representatives from the European Commission and the Eurasian Economic Commission. This report presents the synthesis of three years of multi-disciplinary work

High energy inelastic electron hadron scattering, in peripheral kinematics. Sum rules for hadron form factors

Relations between differential cross section for inelastic scattering of electrons on hadrons and hadron form factors (sum rules) are derived on the basis of analytical properties of heavy photon forward Compton scattering on hadrons. Sum rules relating the slope of form-factors at zero momentum transfer and anomalous magnetic moments of hadrons with some integrals on photo-production on a hadrons is obtained as well. To provide the convergence of these integrals we construct differences of individual sum rules for different hadrons. Universal interaction of Pomeron with nucleons is assumed. We derive the explicit formulae for processes of electro-production on proton and light isobar nuclei. Sudakov's parametrization of momenta, for peripheral kinematics relevant here, is used. The light-cone form of differential cross sections is also discussed. The accuracy of sum rules estimated in frames of point-like hadrons and it is shown to be at the level of precision achievable by experiments. Suggestions and predictions for future experiments are also given.Comment: 18 pages, 5 figure

Charged pair production by photon scattering on a proton

We have investigate the production of lepton and pseudoscalar meson charged pairs by high energy linearly polarized photon–proton scattering in the point–like approximation. The corresponding azimuthal and polar angle distributions on a recoil proton in the inclusive experimental setup have been calculated. The asymmetry Λtot has the values from 0.02 at small values of the polar angle θ up to 0.05 for θ ∼ π/2

Triplet Production by Linearly Polarized Photons

The process of electron-positron pair production by linearly polarized photons is used as a polarimeter to perform mobile measurement of linear photon polarization. In the limit of high photon energies, omega, the distributions of the recoil-electron momentum and azimuthal angle do not depend on the photon energy in the laboratory frame. We calculate the power corrections of order m/omega to the above distributions and estimate the deviation from the asymptotic result for various values of omega.Comment: LaTeX2e, 13 pages, 5 figure files (eps), submitted to Phys. Rev.

Mjerenje linearne polarizacije realnih fotona

A survey of known methods of analyzing linear polarization of high-energy photons is presented. The methods of pair photoproduction in single crystals and in amorphous targets are briefly discussed. The method of measurement of photon linear polarization using azimuthal asymmetry of the recoil electrons from pair photoproduction on electron (triplet photoproduction process) is considered in details. The optimum region of kinematic parameters of emitted particles in which analyzing power increases is discussed. Possibility of using CLAS for the measurement of linear photon polarization by analyzing the recoil-electron distribution in triplet photoproduction process (when shielding magnet is turned off) is considered.Daje se pregled poznatih metoda za određivanje linearne polarizacije visokoenergijskih fotona. Raspravlja se kratko tvorba parova u monokristalima i amorfnim metama. Podrobno se razmatra metoda mjerenja polarizacije određivanjem azimutalne asimetrije elektrona od fototvorbe na elektronima (trojna fototvorba). Raspravlja se najpovoljnije područje kinematičkih parametara izlaznih čestica. Izlaže se mogćcnost primjene CLASa za određivanje linearne polarizacije fotona mjerenjem raspodjele odbijenih elektrona iz trojnog fototvorbenog procesa (za vrijeme mjerenja CLASov magnet bi se isključio)

QED radiative corrections to impact factors

We consider the radiative corrections to the impact factors of electron and photon. According to a generalized eikonal representation the e\bar e scattering amplitude at high energies and fixed momentum transfers is proportional to the electron form factor. But we show that this representation is violated due to the presence of non-planar diagrams. One loop correction to the photon impact factor for small virtualities of the exchanged photon is obtained using the known results for the cross section of the e\bar e production at photon-nuclei interactions.Comment: 8 pp, plain LaTe

Cross-relaxation and phonon bottleneck effects on magnetization dynamics in LiYF4:Ho3+

Frequency and dc magnetic field dependences of dynamic susceptibility in diluted paramagnets LiYF$_4$:Ho$^{3+}$ have been measured at liquid helium temperatures in the ac and dc magnetic fields parallel to the symmetry axis of a tetragonal crystal lattice. Experimental data are analyzed in the framework of microscopic theory of relaxation rates in the manifold of 24 electron-nuclear sublevels of the lowest non-Kramers doublet and the first excited singlet in the Ho$^{3+}$ ground multiplet $^5I_8$ split by the crystal field of S$_4$ symmetry. The one-phonon transition probabilities were computed using electron-phonon coupling constants calculated in the framework of exchange charge model and were checked by optical piezospectroscopic measurements. The specific features observed in field dependences of the in- and out-of-phase susceptibilities (humps and dips, respectively) at the crossings (anti-crossings) of the electron-nuclear sublevels are well reproduced by simulations when the phonon bottleneck effect and the cross-spin relaxation are taken into account