2,527 research outputs found

    Language Identification and Identity

    Get PDF
    В статье рассматривается соотношение понятий этноса, нации и языка на примере языковой политики на Украине.The paper examines the correlation of the concepts of ethnos, nation, and language on the example of the language policy in Ukraine and explores the conceptual content and functional positions of language identification and identity in the process of ethnic identification

    Self-Identification of Donbas Residents

    Get PDF
    В статье рассматривается современное состояние этнической структуры населения Донбасса.The paper is partly an overview and is devoted to the issues of the history and current state of the ethnic structure of the Donbas population and the peculiarities of the identity of the region residents, in particular their eth-nic/national self-identification

    Beam-helicity asymmetries for single-hadron production in semi-inclusive deep-inelastic scattering from unpolarized hydrogen and deuterium targets

    Get PDF
    A measurement of beam-helicity asymmetries for single-hadron production in deep-inelastic scattering is presented. Data from the scattering of 27.6 GeV electrons and positrons off gaseous hydrogen and deuterium targets were collected by the HERMES experiment. The asymmetries are presented separately as a function of the Bjorken scaling variable, the hadron transverse momentum, and the fractional energy for charged pions and kaons as well as for protons and anti-protons. These asymmetries are also presented as a function of the three aforementioned kinematic variables simultaneously

    Transverse-target-spin asymmetry in exclusive ω\omega-meson electroproduction

    Get PDF
    Hard exclusive electroproduction of ω\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 πω\pi\omega transition form factor.Comment: DESY Report 15-14

    Longitudinal double-spin asymmetries in semi-inclusive deep-inelastic scattering of electrons and positrons by protons and deuterons

    Get PDF
    A comprehensive collection of results on longitudinal double-spin asymmetries is presented for charged pions and kaons produced in semi-inclusive deep-inelastic scattering of electrons and positrons on the proton and deuteron, based on the full HERMES data set. The dependence of the asymmetries on hadron transverse momentum and azimuthal angle extends the sensitivity to the flavor structure of the nucleon beyond the distribution functions accessible in the collinear framework. No strong dependence on those variables is observed. In addition, the hadron charge-difference asymmetry is presented, which under certain model assumptions provides access to the helicity distributions of valence quarks

    Bose-Einstein correlations in hadron-pairs from lepto-production on nuclei ranging from hydrogen to xenon

    Get PDF
    Bose-Einstein correlations of like-sign charged hadrons produced in deep-inelastic electron and positron scattering are studied in the HERMES experiment using nuclear targets of 1^1H, 2^2H, 3^3He, 4^4He, N, Ne, Kr, and Xe. A Gaussian approach is used to parametrize a two-particle correlation function determined from events with at least two charged hadrons of the same sign charge. This correlation function is compared to two different empirical distributions that do not include the Bose-Einstein correlations. One distribution is derived from unlike-sign hadron pairs, and the second is derived from mixing like-sign pairs from different events. The extraction procedure used simulations incorporating the experimental setup in order to correct the results for spectrometer acceptance effects, and was tested using the distribution of unlike-sign hadron pairs. Clear signals of Bose-Einstein correlations for all target nuclei without a significant variation with the nuclear target mass are found. Also, no evidence for a dependence on the invariant mass W of the photon-nucleon system is found when the results are compared to those of previous experiments

    Evidence for Quark-Hadron Duality in the Proton Spin Asymmetry A1A_1

    Full text link
    Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1A_1. Longitudinally polarised positrons were scattered off a longitudinally polarised hydrogen target for values of Q2Q^2 between 1.2 and 12 GeV2^2 and values of W2W^2 between 1 and 4 GeV2^2. The average double-spin asymmetry in the nucleon resonance region is found to agree with that measured in deep-inelastic scattering at the same values of the Bjorken scaling variable xx. This finding implies that the description of A1A_1 in terms of quark degrees of freedom is valid also in the nucleon resonance region for values of Q2Q^2 above 1.6 GeV2^2.Comment: 5 pages, 1 eps figure, table added, new references added, in print in Phys. Rev. Let

    First Measurement of the Tensor Structure Function b1b_1 of the Deuteron

    Full text link
    The \Hermes experiment has investigated the tensor spin structure of the deuteron using the 27.6 GeV/c positron beam of \Hera. The use of a tensor polarized deuteron gas target with only a negligible residual vector polarization enabled the first measurement of the tensor asymmetry \At and the tensor structure function \bd for average values of the Bj{\o}rken variable 0.01<0.450.01<0.45 and of the squared four-momentum transfer 0.5GeV2<5GeV20.5 {\rm GeV^2} <5 {\rm GeV^2}. The quantities \At and \bd are found to be non-zero. The rise of \bd for decreasing values of xx can be interpreted to originate from the same mechanism that leads to nuclear shadowing in unpolarized scattering

    Search for an exotic S=-2, Q=-2 baryon resonance at a mass near 1862 MeV in quasi-real photoproduction

    Full text link
    A search for an exotic baryon resonance with S=2,Q=2S=-2, Q=-2 has been performed in quasi-real photoproduction on a deuterium target through the decay channel ΞπΛππpπππ\Xi^- \pi^- \to \Lambda \pi^- \pi^- \to p \pi^- \pi^- \pi^-. No evidence for a previously reported Ξ(1860)\Xi^{--}(1860) resonance is found in the Ξπ\Xi^- \pi^-invariant mass spectrum. An upper limit for the photoproduction cross section of 2.1 nb is found at the 90% confidence level. The photoproduction cross section for the Ξ0(1530)\Xi^{0}(1530) is found to be between 9 and 24 nb
    corecore