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A bstract A comprehensive set of azimuthal single-spin and double-spin asymmetries in semi-inclusive leptoproduction of pions, charged kaons, protons, and antiprotons from transversely polarized protons is presented. These asymmetries include the previously published HERMES results on Collins and Sivers asymmetries, the analysis of which has been extended to include protons and antiprotons and also to an extraction in a three-dimensional kinematic binning and enlarged phase space. They are complemented by corresponding results for the remaining four single-spin and four double-spin asymmetries allowed in the one-photon-exchange approximation of the semi-inclusive deep-inelastic scattering process for target-polarization orientation perpendicular to the direction of the incoming lepton beam. Among those results, significant non-vanishing cos ( ϕ−ϕ S ) modulations provide evidence for a sizable worm-gear (II) distribution, g 1 T q x p T 2 . Most of the other modulations are found to be consistent with zero with the notable exception of large sin ( ϕ S ) modulations for charged pions and K + .

We report on new flavor tagging algorithms developed to determine the quark-flavor content of bottom ( ) mesons at Belle II. The algorithms provide essential inputs for measurements of quark-flavor mixing and charge-parity violation. We validate and evaluate the performance of the algorithms using hadronic decays with flavor-specific final states reconstructed in a data set corresponding to an integrated luminosity of 62.8 fb-1, collected at the resonance with the Belle II detector at the SuperKEKB collider. We measure the total effective tagging efficiency to be εeff=(30.0±1.2(stat)±0.4(syst))%for a category-based algorithm and εeff=(28.8±1.2(stat)±0.4(syst))%for a deep-learning-based algorithm.

An estimate is given of the simulation with the Monte Carlo (MC) method using the signal to background ratios in invariant mass spectra of pion-kaon system for decays of D 0 → K − π + and → K + π − originated from decays of D * + → D 0 π + and D* − → π − at different momentum/angular bins of pions (when pion is coming to the ARICH acceptance) and kaons (kaon is in ARICH acceptance). The tabulated data for mentioned ratios will be used by Belle II collaboration to study the ARICH performance. Then the results of ARICH efficiencies and misidentification probability extracted based on tabulated ratios, will become important ingredient for future physics analysis.

Exclusive [Formula omitted]-meson electroproduction is studied by the HERMES experiment, using the 27.6 GeV longitudinally polarized electron/positron beam of HERA and a transversely polarized hydrogen target, in the kinematic region 1.0 GeV [Formula omitted] 7.0 GeV [Formula omitted], 3.0 GeV [Formula omitted] 6.3 GeV, and [Formula omitted] 0.4 GeV [Formula omitted]. Using an unbinned maximum-likelihood method, 25 parameters are extracted. These determine the real and imaginary parts of the ratios of several helicity amplitudes describing [Formula omitted]-meson production by a virtual photon. The denominator of those ratios is the dominant amplitude, the nucleon-helicity-non-flip amplitude [Formula omitted], which describes the production of a longitudinal [Formula omitted]-meson by a longitudinal virtual photon. The ratios of nucleon-helicity-non-flip amplitudes are found to be in good agreement with those from the previous HERMES analysis. The transverse target polarization allows for the first time the extraction of ratios of a number of nucleon-helicity-flip amplitudes to [Formula omitted]. Results obtained in a handbag approach based on generalized parton distributions taking into account the contribution from pion exchange are found to be in good agreement with these ratios. Within the model, the data favor a positive sign for the [Formula omitted] transition form factor. By also exploiting the longitudinal beam polarization, a total of 71 [Formula omitted] spin-density matrix elements is determined from the extracted 25 parameters, in contrast to only 53 elements as directly determined in earlier analyses.

Recently, in Russian medicine there have been many problems accumulated over the past decades. One of the ways to solve the accumulated problems in the field of health care can be considered the introduction of such an institution of interaction between the government and businesses as public-private partnership (hereinafter – PPP). The article analyzes PPP in health care as a comprehensive study of positive and negative factors that can affect the effectiveness of the development of PPP Institute in the modernization of health care. According to the results of the analysis, the most important strategic priorities of PPP Institute development in the field of health care are identified, which imply the need to create favorable legal, organizational and institutional conditions for effective management of PPP projects in the modernization of health care in order to improve the availability and quality of medical services.

Hard exclusive electroproduction of [Formula omitted] mesons is studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. The amplitudes of five azimuthal modulations of the single-spin asymmetry of the cross section with respect to the transverse proton polarization are measured. They are determined in the entire kinematic region as well as for two bins in photon virtuality and momentum transfer to the nucleon. Also, a separation of asymmetry amplitudes into longitudinal and transverse components is done. These results are compared to a phenomenological model that includes the pion pole contribution. Within this model, the data favor a positive [Formula omitted] transition form factor.

The improved two-scale model is used to perform the fit to the semi-inclusive deep-inelastic scattering (SIDIS) data of HERMES experiment at DESY on nuclear targets. The ratio of hadron multiplicity on nuclear target to the deuterium one is chosen as observable, as usually. The two-parameter’s fit gives satisfactory agreement with the data in term of χ 2 criterium. Best values of parameters are then used to calculate the nuclear multiplicity ratio for the hadrons not included in the fit procedure.

Hard exclusive electroproduction of omega mesons is studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. The amplitudes of five azimuthal modulations of the single-spin asymmetry of the cross section with respect to the transverse proton polarization are measured. They are determined in the entire kinematic region as well as for two bins in photon virtuality and momentum transfer to the nucleon. Also, a separation of asymmetry amplitudes into longitudinal and transverse components is done. These results are compared to a phenomenological model that includes the pion pole contribution. Within this model, the data favor a positive pi omega transition form factor.

The two-scale model and its improved version were used to perform a fit to the HERMES data for the \\(\\nu\\) (the virtual photon energy) and z (the fraction of \\(\\nu\\) carried by hadron) dependences of the nuclear multiplicity ratios for \\(\\pi^ + \\) and \\(\\pi^-\\) mesons electro-produced on two nuclear targets (14N and 84Kr). The quantitative criterion \\(\\chi^2\\) was used for the first time to analyze the results of the model fit to the nuclear multiplicity ratios data. The two-parameter's fit gave satisfactory agreement with the HERMES data. Best values of the parameters were then used to calculate the \\(\\nu\\) and z dependences of the nuclear attenuation for \\(\\pi^0\\), K + , K-, and \\(\\bar{p}\\) produced on the 84Kr target, and also make predictions for \\(\\nu\\), z, and the Q2 (the photon virtuality) dependences of the nuclear attenuation data for those identified hadrons and nuclei that will be published by HERMES.