315 research outputs found

    Electronic spectroscopy of cold ions in a radio-frequency trap

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    The low density of ions in mass spectrometers generally precludes direct absorption measurements. The spectrum of ions can nonetheless be obtained by using resonance two-color photofragmentation or multiphoton photofragmentation techniques. In Basel an ion-trap instrument has been built to measure the electronic spectra of cations at low vibrational and rotational temperatures (20-40 K), as of relevance to astronomical observations. Ions are produced in an electron-impact ion source and are mass selected with a quadrupole filter before being fed into a 22-pole radio-frequency trap. Typically 3000 ions are held for approximately 70 ms, during which the ions are equilibrated to low temperatures through collisions with cryogenically cooled helium gas. Subsequently an electronic transition is induced through excitation with a tunable nanosecond laser. A second UV photon then initiates photofragmentation of the excited ions. Afterward the trap is opened and the fragment ions are mass selected by a second quadrupole and detected. The recently obtained results of the excited states of some polyacetylene cations, caynogen cation, C4H3Cl+ cation in the gas phase are presented

    Relations among higher order values around the world

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    The circular structure of basic human values is the core element of the Schwartz value theory. The structure demonstrated high robustness across cultures. However, the specific correlations between values and the differences in these correlations across countries have received little attention. The current research investigated the within-country correlations between the four higher order values. We estimated the correlations with meta-analytical mixed-effects models based on 10 surveys, on different value instruments, and on data from 104 countries. Analyses revealed theoretically expected negative relations between openness to change and conservation values and between self-transcendence and self-enhancement values. More interestingly, openness to change and self-transcendence values related negatively with each other, as did conservation and self-enhancement. Openness to change and self-enhancement values related predominantly positively, as did conservation and self-transcendence values. Correlations between the adjacent values were weaker in more economically developed countries, revealing higher value complexity of these societies. These findings were consistent across multiple surveys and after controlling for levels of education and income inequality. We concluded that, across most countries, values tend to be organized predominantly in line with the Social versus Person Focus opposition, whereas the Growth versus Self-Protection opposition is pronounced only in more economically developed countries.info:eu-repo/semantics/acceptedVersio

    Method and Experimental Setup for the Study of the Local Current Distribution in Conducting Micro-and Nanostructures

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    The method for the study of the spatial distribution of current in micro-and nanostructures on the measured magnetic field is presented. The methods of studies the magnetic field distribution of conducting nanostructures by passing a transport current are considered. The technique of current recovery from experimental data is offered. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3522

    Continuation of the exponentially small transversality for the splitting of separatrices to a whiskered torus with silver ratio

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    We study the exponentially small splitting of invariant manifolds of whiskered (hyperbolic) tori with two fast frequencies in nearly-integrable Hamiltonian systems whose hyperbolic part is given by a pendulum. We consider a torus whose frequency ratio is the silver number Ω=21\Omega=\sqrt{2}-1. We show that the Poincar\'e-Melnikov method can be applied to establish the existence of 4 transverse homoclinic orbits to the whiskered torus, and provide asymptotic estimates for the tranversality of the splitting whose dependence on the perturbation parameter ε\varepsilon satisfies a periodicity property. We also prove the continuation of the transversality of the homoclinic orbits for all the sufficiently small values of ε\varepsilon, generalizing the results previously known for the golden number.Comment: 17 pages, 2 figure

    Lowering the Light Speed Isotropy Limit: European Synchrotron Radiation Facility Measurements

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    The measurement of the Compton edge of the scattered electrons in GRAAL facility in European Synchrotron Radiation Facility (ESRF) in Grenoble with respect to the Cosmic Microwave Background dipole reveals up to 10 sigma variations larger than the statistical errors. We now show that the variations are not due to the frequency variations of the accelerator. The nature of Compton edge variations remains unclear, thus outlining the imperative of dedicated studies of light speed anisotropy

    A proposed measurement of the ß asymmetry in neutron decay with the Los Alamos Ultra-Cold Neutron Source

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    This article reviews the status of an experiment to study the neutron spin-electron angular correlation with the Los Alamos Ultra-Cold Neutron (UCN) source. The experiment will generate UCNs from a novel solid deuterium, spallation source, and polarize them in a solenoid magnetic field. The experiment spectrometer will consist of a neutron decay region in a solenoid magnetic field combined with several different detector possibilities. An electron beam and a magnetic spectrometer will provide a precise, absolute calibration for these detectors. An A-correlation measurement with a relative precision of 0.2% is expected by the end of 2002

    Spurious states in the Faddeev formalism for few-body systems

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    We discuss the appearance of spurious solutions of few-body equations for Faddeev amplitudes. The identification of spurious states, i.e., states that lack the symmetry required for solutions of the Schroedinger equation, as well as the symmetrization of the Faddeev equations is investigated. As an example, systems of three and four electrons, bound in a harmonic-oscillator potential and interacting by the Coulomb potential, are presented.Comment: 11 pages. REVTE

    A new limit on the light speed isotropy from the GRAAL experiment at the ESRF

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    When the electrons stored in the ring of the European Synchrotron Radiation Facility (ESRF, Grenoble) scatter on a laser beam (Compton scattering in flight) the lower energy of the scattered electron spectra, the Compton Edge (CE), is given by the two body photon-electron relativistic kinematics and depends on the velocity of light. A precision measurement of the position of this CE as a function of the daily variations of the direction of the electron beam in an absolute reference frame provides a one-way test of Relativistic Kinematics and the isotropy of the velocity of light. The results of GRAAL-ESRF measurements improve the previously existing one-way limits, thus showing the efficiency of this method and the interest of further studies in this direction.Comment: Proceed. MG12 meeting, Paris, July, 200

    ПОЗДНЕПАЛЕОЗОЙСКИЙ КОНТРАСТНЫЙ МАГМАТИЗМ ВОСТОЧНОЙ ЧАСТИ КААХЕМСКОГО МАГМАТИЧЕСКОГО АРЕАЛА (ЦЕНТРАЛЬНО-АЗИАТСКИЙ СКЛАДЧАТЫЙ ПОЯС)

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    Based on the isotope-geochronological (zircons, U-Pb method), petrogeochemical, and structural and petrologic data, the following paper provides a detailed description of the characteristics of the Late Paleozoic basic and granitoid magmatism in the eastern part of the Kaakhem magmatic area (Eastern Tuva). During the formation of the Shivey alkaline-granitoid and Chadal gabbroid massifs in the period of 292–283 Ma, there were revealed two stages of contrasting magmatism. The early stage is characterized by the formation of plutonic mingling structures and intermediate rocks. Deformation structures, widespread in the early-mingling rocks, are superimposed and formed in extensional regime. At a later stage, there occurred a sequential intrusion of salic and mafic magmas into the zones of local extension in the early-mingling host rocks. A similar petrogeochemical composition of basic rocks of the early and late mingling indicates that they all formed from enriched magma. Granosyenites and granites are derived from melting of tonalities and metasedimentary rocks with a significant contribution of the mantle component. The simultaneous formation of the Chadal gabbroid and Shivei granitoid massifs took place at the intraplate stage of the development of geological structures of Eastern Tuva in the Late Paleozoic.В настоящей работе на основе изотопно-геохронологических (цирконы, U-Pb метод), петрогеохимических и структурно-петрологических данных приводится характеристика позднепалеозойского магматизма Каахемского ареала (Восточная Тува). Выявлены два этапа контрастного по составу магматизма при становлении Шивейского щелочно-гранитоидного и Чадалского габброидного массивов в период 292–283 млн лет. Ранний этап характеризуется формированием структур плутонического минглинга и образованием пород промежуточного состава. Деформационные структуры, широко распространенные в породах раннего минглинга, имеют наложенный характер и формировались в обстановках растяжения. На позднем этапе последовательное внедрение салических и мафических магм происходило в зоны локального растяжения во вмещающих породах раннего минглинга. Мафические породы раннего и позднего минглинга идентичны по петрогеохимическому составу, что указывает на их происхождение из единого глубинного обогащенного источника. Образование граносиенитов и гранитов связано с плавлением тоналитов и метаосадочных пород со значительным вкладом мантийного компонента. Одновременное становление Чадалского габброидного и Шивейского гранитоидного массивов происходило на внутриплитном этапе развития геологических структур Восточной Тувы в позднем палеозое
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