1,292 research outputs found

    The gluon content of the η\eta and η\eta^{\prime} mesons and the ηγ\eta\gamma, ηγ\eta^{\prime}\gamma electromagnetic transition form factors

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    We compute power-suppressed corrections to the \eta\gamma and \eta^{\prime}\gamma transition form factors Q^2F_{\eta(\eta^{\prime})\gamma}(Q^2) arising from the end point regions x \to 0,1 by employing the infrared-renormalon approach. The contribution to the form factors from the quark and gluon content of the \eta,\eta^{\prime} mesons is taken into account using for the \eta-\eta^{\prime} mixing the SU_f(3) singlet \eta_1 and octet \eta_8 basis. The theoretical predictions obtained this way are compared with the corresponding CLEO data and restrictions on the input parameters (Gegenbauer coefficients) B_2^q(\eta_1), B_2^g(\eta_1), and B_2^q(\eta_8) in the distribution amplitudes for the \eta_1,\eta_8 states with one nonasymptotic term are deduced. Comparison is made with the results from QCD perturbation theory.Comment: 25 pages, RevTeX4 used. 9 figures as EPS files. Text significantly changed to include variation of theoretical parameters. Figures modified. Corrected typo in equation (34) and trivial mistake in β1\beta_1-coefficient. References added. Conclusions unchange

    Пассажирские перевозки и оптимизация городской маршрутной сети

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    [For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT The authors propose measures to optimize the urban route network of passenger transport. In accordance with the tasks of optimization, a program and methodology for the survey of passenger flows, a more rational scheme for the route network, a transport macro model for the city, a passenger navigation system for the GLONASS or GLONASS/ GPS monitoring system, security monitoring systems and mobile objects management were developed. Keywords: public transport, urban route network, passenger transportation, optimization, monitoring, GLONASS, macro model, passenger flows.Текст аннотации на англ. языке и полный текст статьи на англ. языке находится в прилагаемом файле ПДФ (англ. версия следует после русской версии).Авторы предлагают меры по оптимизации городской маршрутной сети пассажирского транспорта. В соответствии с задачами оптимизации разработаны программа и методика обследования пассажиропотоков, более рациональная схема маршрутной сети, транспортная макромодель города, предусмотрено внедрение в сфере пассажирских перевозок навигационной системы мониторинга ГЛОНАСС или ГЛОНАСС/GPS, системы мониторинга безопасности и управления подвижными объектами
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