Double logarithmical corrections to beam asymmetry in polarized electron-proton scattering

The up-down asymmetry in transversally polarized electron proton scattering is induced by the interference between one and two photon exchange amplitudes. Inelastic intermediate hadronic states (different from one-proton state) of the two photon exchange amplitude give rise to contributions containing the square of "large logarithm" (logarithm of the ratio of the transferred momentum to the electron mass). We investigate the presence of such contributions in higher orders of perturbation theory. The relation with the case of zero transfer momentum is explicitly given. The mechanism of cancellation of infrared singularities is discussed.Comment: 9 pages, 8 figure

Testing the RRPP vertex of effective Regge action

In frames of effective Regge action the vertices describing conversion of two reggeized gluons to one two and three ordinary gluons was constructed. The self-consistency: Bose symmetry and gauge invariance properties checks was shown to be fulfilled. The simplest one with creation of a single gluon was intensively verified in programs of experimental and theoretical treatment since it determine the kernel of of the known BFKL equation. Here we discuss the possibility to check the vertex with creation of two real gluons, which can reveal itself in process of scalar mesons production in high energy peripheral nucleons collisions. We show that the mechanisms which include emission of two gluons in the same effective vertex contribution dominate compared with one with the creation of two separate gluons. Numerical estimations of cross section of pair of charged pions production for LHC facility give the value or order $10 mb$. As well we estimate the excess of production of positively charged muons (as a decay of pions) created by cosmic ray proton collisions with the atmosphere gas nuclei to be in a reasonable agreement with modern data.Comment: 9 page

Electron-positron pair production by linearly polarized photon in the nuclear field

Process of lepton pair production by polarized photon on nuclei can be used to measure the degree of linear polarization of high energy photon. The differential cross section and the analyzing power are calculated with taking into account higher powers of expansion on $Z\alpha$. Pure Coulomb and screened potential are considered.Comment: 12 page