1,328 research outputs found

    Calculation of resonances in the Coulomb three-body system with two disintegration channels in the adiabatic hyperspherical approach

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    The method of calculation of the resonance characteristics is developed for the metastable states of the Coulomb three-body (CTB) system with two disintegration channels. The energy dependence of K-matrix in the resonance region is calculated with the use of the stabilization method. Resonance position and partial widths are obtained by fitting the numerically calculated K(E)-matrix with the help of the generalized Breit-Wigner formula.Comment: Latex, 11 pages with 5 figures and 2 table

    Multi-level Dynamical Systems: Connecting the Ruelle Response Theory and the Mori-Zwanzig Approach

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    In this paper we consider the problem of deriving approximate autonomous dynamics for a number of variables of a dynamical system, which are weakly coupled to the remaining variables. In a previous paper we have used the Ruelle response theory on such a weakly coupled system to construct a surrogate dynamics, such that the expectation value of any observable agrees, up to second order in the coupling strength, to its expectation evaluated on the full dynamics. We show here that such surrogate dynamics agree up to second order to an expansion of the Mori-Zwanzig projected dynamics. This implies that the parametrizations of unresolved processes suited for prediction and for the representation of long term statistical properties are closely related, if one takes into account, in addition to the widely adopted stochastic forcing, the often neglected memory effects.Comment: 14 pages, 1 figur

    Fragmentation channels of relativistic 7^7Be nuclei in peripheral interactions

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    Nuclei of 7^7Li were accelerated at the JINR Nuclotron. After the charge-exchange reaction involving these nuclei at an external target a second 7^7Be beam of energy 1.23A GeV was formed. This beam was used to expose photo-emulsion chambers. The mean free path for inelastic 7^7Be interactions in emulsion λ\lambda=14.0±\pm0.8 cm coincides within the errors with those for 6^6Li and 7^7Li nuclei. More than 10% of the 7^7Be events are associated with the peripheral interactions in which the total charge of the relativistic fragments is equal to the charge of the 7^7Be and in which charged mesons are not produced. An unusual ratio of the isotopes is revealed in the composition of the doubly charged 7^7Be fragments: the number of 3^3He fragments is twice as large as that of 4^4He fragments. In 50% of peripheral interactions, a 7^7Be nucleus decays to two doubly charged fragments. The present paper gives the channels of the 7^7Be fragmentation to charged fragments. In 50% of events, the 7^7Be fragmentation proceeds only to charged fragments involving no emission of neutrons. Of them, the 3^3He+4^4He channel dominates, the 4^4He+d+p and 6^6Li+pchannels constitute 10% each. Two events involving no emission of neutrons are registered in the 3-body 3^3He+t+p and 3^3He+d+d channels. The mean free path for the coherent dissociation of relativistic 7^7Be nuclei to 3^3He+4^4He is 7±\pm1 m. The particular features of the relativistic 7^7Be fragmentation in such peripheral interactions are explained by the 3^3He+4^4He 2-cluster structure of the 7^7Be nucleus.Comment: 10 pages, 3 figures, 3 tables, conference: Conference on Physics of Fundamental Interactions, Moscow, Russia, 5-9 Dec 200

    Assessment of efficacy and safety of the herbal medicinal product BNO 1016 in chronic rhinosinusitis

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    Background: The objective of this clinical trial (CRS-02) was to assess the efficacy, safety and tolerability of two dosages of the herbal medicinal product BNO 1016 (Sinupret extract) in patients with chronic rhinosinusitis (CRS). Methodology: 929 patients suffering from CRS were enrolled in this randomised placebo-controlled trial with a treatment period of 12 weeks. The primary endpoint was the mean Major Symptom Score (MSS) in week 8 and week 12 compared to placebo. Secondary endpoints included further MSS related parameters and responder rates over time. Pharmacoeconomic endpoints were also analysed. Finally, safety and tolerability were evaluated. Results: Sinupret extract was not superior over placebo regarding the primary endpoint. However, the results of the secondary endpoints showed a clear trend towards superior efficacy. Therefore, additional post-hoc sensitivity analyses were performed in patients with a baseline MSS > 9 and persistence of disease > 1 year diagnosed by specialists in otorhinolaryngology.Those patients significantly benefited from Sinupret extract. Therapy was superior for the primary endpoint analysis. Patients were less impaired with respect to work and daily activities. A good safety and tolerability of Sinupret extract was assured in all patients. Conclusions: Sinupret extract can safely be administered in patients with CRS. Although the primary endpoint of the study was not significant, a post-hoc subgroup analysis in patients whose disease was diagnosed by a specialist revealed a pronounced treatment effect. Effects in that subgroup were even stronger with longer disease persistence and stronger severity

    Joule Heating and Current-Induced Instabilities in Magnetic Nanocontacts

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    We consider the electrical current through a magnetic point contact in the limit of a strong inelastic scattering of electrons. In this limit local Joule heating of the contact region plays a decisive role in determining the transport properties of the point contact. We show that if an applied constant bias voltage exceeds a critical value, the stationary state of the system is unstable, and that periodic, non-harmonic oscillations in time of both the electrical current through the contact and the local temperature in the contact region develop spontaneously. Our estimations show that the necessary experimental conditions for observing such oscillations with characteristic frequencies in the range 108÷10910^8 \div 10^9 Hz can easily be met. We also show a possibility to manipulate upon the magnetization direction of a magnetic grain coupled through a point contact to a bulk ferromagnetic by exciting the above-mentioned thermal-electric oscillations.Comment: 9 pages, 6 figures, submitted to Physical Review
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