Quark-diquark model for p(\bar p)-p elastic scattering at high energies

A model for elastic scattering of protons at high energies based on the quark-diquark representation of the proton is discussed. The predictions of the model are compared with experimental data for the differential elastic cross-sections from available databasesComment: 4 pages, 5 figure

Diffractive photoproduction of meson pairs in the S\"oding model

We consider the diffractive photoproduction of $\pi^+\pi^- , K^+K^- , D^+D^-$ meson pairs with high masses and transverse momenta in the framework of the S\"oding model. The total and differential cross sections are calculated for these processes. The role of the form factors is stressed.Comment: 7 pages, 7 figures, latex; Talk at DIS 97 Workshop (Chicago, 1997

The effect of different baryons impurities

We demonstrate the different effect of different baryons impurities on the static properties of nuclei within the framework of the relativistic mean-field model. Systematic calculations show that $\Lambda_c^+$ and $\Lambda_b$ has the same attracting role as $\Lambda$ hyperon does in lighter hypernuclei. $\Xi^-$ and $\Xi_c^0$ hyperon has the attracting role only for the protons distribution, and has a repulsive role for the neutrons distribution. On the contrary, $\Xi^0$ and $\Xi^+_c$ hyperon attracts surrounding neutrons and reveals a repulsive force to the protons. We find that the different effect of different baryons impurities on the nuclear core is due to the different third component of their isospin.Comment: 9 page

The effects of the small t properties of hadronic scattering amplitude on the determination its real part

Taking into account the different forms of the Coulomb-hadron interference phase and the possible spin-flip contribution the new analysis of the experimental data of the proton-antiproton elastic scattering at $3.8 < p_L <6.0 \$GeV/c and small momentum transfer is carried out. It is shown that the size of the spin-flip amplitude can be determined from the form of the differential cross sections at small $t$, and the deviation of $\rho(s,t)$ obtained from the examined experimental data of the $p\bar{p}$ scattering from the analysis \cite{Kroll}, based on the dispersion relations, is conserved in all xamined assumptions. The analysis of the proton-proton elastic scattering at $9 < p_L < 70 \$GeV/c also shows the impact of the examined effects on the form of the differential cross sections.Comment: 13 pages, 3 figure

Pion and Kaon Polarizabilities and Radiative Transitions

CERN COMPASS plans measurements of gamma-pi and gamma-K interactions using 50-280 GeV pion (kaon) beams and a virtual photon target. Pion (kaon) polarizabilities and radiative transitions will be measured via Primakoff effect reactions such as pi+gamma->pi'+gamma and pi+gamma->meson. The former can test a precise prediction of chiral symmetry; the latter for pi+gamma->a1(1260) is important for understanding the polarizability. The radiative transition of a pion to a low mass two-pion system, pi+gamma->pi+pi0, can also be studied to measure the chiral anomaly amplitude F(3pi) (characterizing gamma->3pi), arising from the effective Chiral Lagrangian. We review here the motivation for the above physics program. We describe the beam, target, detector, and trigger requirements for these experiments. We also describe FNAL SELEX attempts to study related physics via the interaction of 600 GeV pions with target electrons. Data analysis in progress aims to identify the reactions pi+e->pi'+e'+pi0 related to the chiral anomaly, and pi+e->pi'+e'+gamma related to pion polarizabilities.Comment: 16 pages, 6 figures, Latex Springer-Verlag style Tel Aviv U. Preprint TAUP-2469-97, Contribution to the Workshop on Chiral Dynamics Theory and Experiment, U. of Mainz, Sept. 1-5, 1997, to be published in Springer-Verlag, Eds. A. Bernstein, Th. Walcher, 199

Оценка экологической опасности авиационных событий на воздушном транспорте

The article offers to consider the anthropogenous and emergency zones arising as a result of aviation events as geotechnical systems. It also gives classification signs of basic main levels of such systems and typical examples of transport objects on which such aviation events take place. The article offeres the hierarchy of the system levels, excisting in the formed as extreme ecological zones. The harm caused by aviation event to environment, is estimated. The actuality of incrasing the negative effect on the environment on the air transport is being proved.В статье предлагается рассматривать возникающие при авиационных событиях антропогенно-аварийные зоны как геотехнические системы. Приводятся классификационные признаки основных уровней таких систем и характерные примеры транспортных объектов, на которых происходят такие авиационные события. Предлагается иерархия уровней систем, образующихся в виде экстремальных экологических зон. Оценивается вред авиационного события, наносимый окружающей среде. Обосновывается актуальность повышения безопасности полетов как важного метода снижения негативного воздействия на окружающую среду на воздушном транспорте