Relativistic corrections to \eta_c-pair production in high energy proton-proton collisions

On the basis of perturbative QCD and the relativistic quark model we calculate relativistic corrections to the double $\eta_c$ meson production in proton-proton interactions at LHC energies. Relativistic terms in the production amplitude connected with the relative motion of heavy quarks and the transformation law of the bound state wave functions to the reference frame of moving charmonia are taken into account. For the gluon and quark propagators entering the amplitude we use a truncated expansion in relative quark momenta up to the second order. Relativistic corrections to the quark bound state wave functions are considered by means of the Breit-like potential. It turns out that the examined effects decrease total nonrelativistic cross section more than two times and on 20 percents in the rapidity region of LHCb detector.Comment: 12 pages, 3 figure

Pair double heavy diquark production in high energy proton-proton collisions

On the basis of perturbative QCD and relativistic quark model we calculate relativistic and bound state corrections in the production processes of a pair of double heavy diquarks. Relativistic factors in the production amplitude connected with the relative motion of heavy quarks and the transformation law of the bound state wave function to the reference frame of the moving S-wave diquark bound states are taken into account. For the gluon and quark propagators entering the amplitudes we use a truncated expansion in relative quark momenta up to the second order. Relativistic corrections to the quark-quark bound state wave functions in the rest frame are considered by means of the Breit-like potential. It turns out that the examined effects significantly decrease nonrelativistic cross sections.Comment: 20 pages, 5 figure

Determining the size of the proton

A measurement of the Lamb shift of 49,881.88(76) GHz in muonic hydrogen in conjunction with theoretical estimates of the proton structure effects was recently used to deduce an accurate but rather small radius of the proton. Such an important shift in the understanding of fundamental values needs reconfirmation. Using a different approach with electromagnetic form factors of the proton, we obtain a new expression for the transition energy, $\Delta = E_{2P_{{3}/{2}}}^{f=2} - E_{2S_{{1}/{2}}}^{f=1}$, in muonic hydrogen and deduce a proton radius, $r_p = 0.831$ fm.Comment: 20 pages LaTe

Self-energy correction to the bound-electron g factor in H-like ions

The one-loop self-energy correction to the 1s electron g factor is evaluated to all orders in Z\alpha with an accuracy, which is essentially better than that of previous calculations of this correction. As a result, the uncertainty of the theoretical prediction for the bound-electron g factor in H-like carbon is reduced by a factor of 3. This improves the total accuracy of the recent electron-mass determination [Beier et al. Phys. Rev. Lett. 88, 011603 (2002)]. The new value of the electron mass is found to be m_e = 0.000 548 579 909 3(3) u

Nucleus polarizability contribution to the hydrogen-deuterium isotope shift

The correction to the hydrogen-deuterium isotope shift due to the proton and deuteron polarizability is evaluated on the basis of modern experimental data on the structure functions of inelastic lepton-nucleus scattering. The numerical value of this contribution is equal 63\pm 12 Hz.Comment: 5 page

Development of enterprise reputation management in the sphere of medical services

Topicality of the theme is determined by the increased role and influence of patients on the formation of the reputation of healthcare organisations in the conditions of active use of social networks by patients as a source of information when choosing a doctor. The purpose of the article was to identify the specificity and stages of the process of development of enterprise reputation management in the sphere of medical services. In the process of achieving this purpose there were used such scientific research methods as logic generalisation, comparative analysis, synthesis, graphical method as well. For gathering the feedback from the patients, the survey method based on quantitative analysis of responses and net promoter score was used. The specifics of medical services and their types were substantiated as the main results of the research, as well as elements that determine the value of medical services for the consumers. The features and trends of reputation management in the field of medical services have been considered and the stages of the process of development of reputation management of the healthcare organisation have been substantiated. As a result of the propositions, considered in the article, it has become possible to solve the reputational contradictions at enterprises in the field of medical services. With the purpose of improving reputational management the algorithm for the application of Search engine reputation management technology elements was developed for the work with consumers’ feedback. Practical meaning of the results is in increasing the effectiveness of reputational management and its development due to the implementation of elaborated algorithm into the process of everyday work with clients of healthcare organisation. It can be the basis for planning changes in business processes and operational management as well as for optimisation of the use of resource

A spectral characterization of skeletal maps

We prove that a map between two realcompact spaces is skeletal if and only if it is homeomorphic to the limit map of a skeletal morphism between ω-spectra with surjective limit projections