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

Feynman rules for effective Regge action

Starting from the gauge invariant effective action in the quasi-multi-Regge kinematics (QMRK), we obtain the effective reggeized gluon (R) -- particle (P) vertices of the following types: $RPP$, $RRP$, $RRPP$, $RPPP$, $RRPPP$, and $RPPPP$, where the on-mass-shell particles are gluons, or sets of gluons with small invariant masses. The explicit expressions satisfying the Bose-symmetry and gauge invariance conditions are obtained. As a comment to the Feynman rules for derivation of the amplitudes in terms of effective vertices we present a ``vocabulary'' for practitioners.Comment: REVTeX, 21 pages, 10 figure

A model for the Q2Q^2 dependence of polarized structure functions

We present an update of a phenomenological model for the spin dependent structure functions $g_1(x,Q^2)$ of the proton and neutron. This model is based on a broken SU(6) wavefunction parametrized by the unpolarized structure functions. The two free parameters of the model are choosen to fulfill the Bjorken and Ellis--Jaffe sum rules. The model respects isospin symmetry and has zero strange sea polarization. Using new values for $F/D$ from hyperon beta decay the resulting $Q^2$ dependent asymmetries $A_1$ are in perfect agreement with the existing data. Therefore we do not see any evidence for a ``spin crisis''. With two choices for $g_2$ the $Q^2$ dependence of $A_1(x,Q^2)$ and $A_2(x,Q^2)\sqrt{Q^2}/M$ is predicted and shown to be small for both cases.Comment: 18 pages and 11 figures as uudecoded ps file

Charged-particle distributions in √s=13 TeV pp interactions measured with the ATLAS detector at the LHC

Charged-particle distributions are measured in proton–proton collisions at a centre-of-mass energy of 13 TeV, using a data sample of nearly 9 million events, corresponding to an integrated luminosity of 170 μb−1170 μb−1, recorded by the ATLAS detector during a special Large Hadron Collider fill. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity and the dependence of the mean transverse momentum on the charged-particle multiplicity are presented. The measurements are performed with charged particles with transverse momentum greater than 500 MeV and absolute pseudorapidity less than 2.5, in events with at least one charged particle satisfying these kinematic requirements. Additional measurements in a reduced phase space with absolute pseudorapidity less than 0.8 are also presented, in order to compare with other experiments. The results are corrected for detector effects, presented as particle-level distributions and are compared to the predictions of various Monte Carlo event generators

Charged-particle distributions at low transverse momentum in √<i>s</i>=13 TeV <i>pp</i> interactions measured with the ATLAS detector at the LHC

Measurements of distributions of charged particles produced in proton-proton collisions with a centre-of-mass energy of 13 TeV are presented. The data were recorded by the ATLAS detector at the LHC and correspond to an integrated luminosity of 151 [Formula: see text]. The particles are required to have a transverse momentum greater than 100 MeV and an absolute pseudorapidity less than 2.5. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity and the dependence of the mean transverse momentum on multiplicity are measured in events containing at least two charged particles satisfying the above kinematic criteria. The results are corrected for detector effects and compared to the predictions from several Monte Carlo event generators

Catalytic membrane in reduction of aqueous nitrates: operational principles and catalytic performance

The catalytic membrane with palladium-copper active component supported over the macroporous ceramic membrane, and a series of γ-Al 2O 3 supported Pd-Cu catalysts were prepared and investigated. In reduction of nitrate ions by hydrogen in water at ambient temperature, pronounced internal diffusion limitations of the reaction rate were observed for Pd-Cu/Al 2O 3 catalysts. The catalytic membrane with Pd-Cu active component deposited over the macroporous ceramic membrane support was employed to minimize the diffusion limitations. Multifold increase in the observed catalytic activity was registered for the catalytic membrane operated with the forced flow of the reaction solution through the membrane, as compared to the value achieved at the same conditions, but in the absence of the forced flow (i.e. when the membrane porous space was accessible to the reactants due to diffusion only). These improvements are attributed to the intensification of the intraporous mass transfer attainable with the reactants forced flow in the membrane pores. The concept of catalytic membrane reactors explored in this study offers a new means to improve catalytic performance in the processes where internal diffusion limitations must be minimized and the use of finely dispersed catalysts is not desired

Catalytic membrane in denitrification of water: a means to facilitate intraporous diffusion of reactants

The series of mono- and bi-metallic catalysts with Pd and/or Cu supported over γ-Al 2O 3 was investigated with respect to reduction of nitrate and nitrite ions in water by hydrogen. Pronounced limitations of catalytic performance due to intraporous diffusion of the reactants were observed in the reaction. Catalytic membrane containing the Pd-Cu active component supported over macroporous ceramic membrane-support was prepared, investigated and applied to facilitate the intraporous mass transfer. Forced flow of the reacting solution through the membrane was revealed to increase the effective catalytic activity. The approach explored in this study offers a cost-efficient alternative to the conventional concept of catalytic water denitrification process in a slurry reactor, presuming fixed-bed type operation with macroporous catalytic membranes at high level of catalytic activity. (C) 2000 Elsevier Science B.V. All rights reserved. | The series of mono- and bi-metallic catalysts with Pd and/or Cu supported over γ-Al 2O 3 was investigated with respect to reduction of nitrate and nitrite ions in water by hydrogen. Pronounced limitations of catalytic performance due to intraporous diffusion of the reactants were observed in the reaction. Catalytic membrane containing the Pd-Cu active component supported over macroporous ceramic membrane-support was prepared, investigated and applied to facilitate the intraporous mass transfer. Forced flow of the reacting solution through the membrane was revealed to increase the effective catalytic activity. The approach explored in this study offers a cost-efficient alternative to the conventional concept of catalytic water denitrification process in a slurry reactor, presuming fixed-bed type operation with macroporous catalytic membranes at high level of catalytic activity