935 research outputs found
The contribution of axial-vector mesons to hyperfine structure of muonic hydrogen
The contribution from the axial-vector meson exchange to the potential of the
muon-proton interaction in muonic hydrogen induced by anomalous axial-vector
meson coupling to two photon state is calculated. It is shown that such
contribution to the hyperfine splitting in muonic hydrogen is large and
important for a comparison with precise experimental data. In the light of our
result, the proton radius "puzzle" is discussed.Comment: 14 pages, 2 figure
The correction of hadronic nucleus polarizability to hyperfine structure of light muonic atoms
The calculation of hadronic polarizability contribution of the nucleus to
hyperfine structure of muonic hydrogen and helium is carried out within the
unitary isobar model and experimental data on the polarized structure functions
of deep inelastic lepton-proton and lepton-deuteron scattering. The calculation
of virtual absorption cross sections of transversely and longitudinally
polarized photons by nucleons in the resonance region is performed in the
framework of the program MAID.Comment: 8 pages, 3 figures, Talk presented at 23th International Workshop on
High Energy Physics and Quantum Field Theory (QFTHEP 2017
Corrections of two-photon interactions in the fine and hyperfine structure of the P-energy levels of muonic hydrogen
In the framework of the quasipotential method in quantum electrodynamics we
calculate corrections to the nuclear structure proportional to from
two-photon exchange amplitudes in the fine and hyperfine structure of P-states
in muonic hydrogen, as well as the photon-photon interaction amplitudes,
leading to the exchange of the axial vector meson. In constructing the
quasipotential of the muon-nucleus interaction, we use the method of projection
operators on states of two particles with a definite spin and total angular
momentum. Analytical calculation of the matrix elements is performed and
contributions to the fine and hyperfine structure of the and
levels are obtained.Comment: 16 pages, 2 figure
The light-by-light contribution to the muon anomalous magnetic moment from the axial-vector mesons exchanges within the nonlocal quark model
The contribution of axial-vector mesons to the muon's anomalous magnetic
moment through a light-by-light process is considered within a nonlocal quark
model. The model is based on a four-quark interaction with scalar--pseudoscalar
and vector--axial-vector sectors. While the transverse component of the
axial-vector corresponds to a spin-1 particle, the unphysical longitudinal
component is mixed with a pseudoscalar meson. The model parameters are
re-fitted to the pion properties in the presence of pi-a_1 mixing. The obtained
estimation for the light-by-light contribution of a_1+f_1 mesons is
(3.6+-1.8)*10^{-11}.Comment: 18 pages, 10 figures, final version accepted for publication in
Physical Review
Implementation of the Russian state armaments program 2011-2020 : economic and financial analysis
The State Armaments Programme (SAP) is a set of industrial, military, political, economic and financial measures aimed at the increase in the country’s defense capacity. The subject of economic analysis of this article is the SAP-2020 adopted in December 2010 and covers a period from 2011 to 2020 which is now at the final stage of its implementation.
On studying the SAP-2020 the authors revealed such key indicators as economic viability and financial efficiency of programme implementation. A comparative analysis of budget funding of the similar US programme was conducted and statistical data supporting the main findings of the study were introduced.
The authors used a wide range of methodological tools in the course of the study. The method of economic analysis, the method of structural analysis, the statistical method and the method of mathematical comparison were used.peer-reviewe
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