3,276 research outputs found

    The Complex X-ray Spectrum of the Sefyert 1.5 Source NGC 6860

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    The X-ray spectrum of the Seyfert 1.5 source NGC 6860 is among the most complex of the sources detected in the Swift Burst Alert Telescope all-sky survey. A short XMM-Newton follow-up observation of the source revealed a flat spectrum both above and below 2 keV. To uncover the complexity of the source, in this paper we analyze both a 40 ks Suzaku and a 100 ks XMM-Newton observation of NGC 6860. While the spectral state of the source changed between the newer observations presented here and the earlier short XMM-Newton spectrum - showing a higher flux and steeper power law component - the spectrum of NGC 6860 is still complex with clearly detected warm absorption signatures. We find that a two component warm ionized absorber is present in the soft spectrum, with column densities of about 10^20 and 10^21 cm$^-2, ionization parameters of xi = 180 and 45 ergs cm s^-1, and outflow velocities for each component in the range of 0-300 km s^-1. Additionally, in the hard spectrum we find a broad (approx 11000 km s^-1) Fe K-alpha emission line, redshifted by approx 2800 km s^-1.Comment: 35 pages, 9 figures, Accepted to Ap

    Macroeconomic Adjustment and Foreign Trade of Centrally Planned Economies

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    This empirical study stresses the underlying macroeconomic forces which determine foreign trade flows in CPEs. The general specification includes a planners' demand equation for the volume of imports, a planners' supply equation for the volume of exports, and a rest-of-world demand equation for the export price level. The planners' behavioural equations include variables for activity levels, trade balance constraints, prices, and domestic excess demand. The import price is exogenous. This simultaneous equation model is estimated on annual data from the mid-1950s to the mid-1970s, for Czechoslovakia, the GDR, Hungary, and Poland. Maximum likelihood estimation in a nested hypothesis testing framework allows selection of restricted versions of the general model for each country. Estimated price elasticities accord with the underlying theory, and the excess demand variables perform well.

    On the reversible extraction of classical information from a quantum source

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    Consider a source E of pure quantum states with von Neumann entropy S. By the quantum source coding theorem, arbitrarily long strings of signals may be encoded asymptotically into S qubits/signal (the Schumacher limit) in such a way that entire strings may be recovered with arbitrarily high fidelity. Suppose that classical storage is free while quantum storage is expensive and suppose that the states of E do not fall into two or more orthogonal subspaces. We show that if E can be compressed with arbitrarily high fidelity into A qubits/signal plus any amount of auxiliary classical storage then A must still be at least as large as the Schumacher limit S of E. Thus no part of the quantum information content of E can be faithfully replaced by classical information. If the states do fall into orthogonal subspaces then A may be less than S, but only by an amount not exceeding the amount of classical information specifying the subspace for a signal from the source.Comment: 22 pages, Latex2e, journal versio

    Structure of states which satisfy strong subadditivity of quantum entropy with equality

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    We give an explicit characterisation of the quantum states which saturate the strong subadditivity inequality for the von Neumann entropy. By combining a result of Petz characterising the equality case for the monotonicity of relative entropy with a recent theorem by Koashi and Imoto, we show that such states will have the form of a so-called short quantum Markov chain, which in turn implies that two of the systems are independent conditioned on the third, in a physically meaningful sense. This characterisation simultaneously generalises known necessary and sufficient entropic conditions for quantum error correction as well as the conditions for the achievability of the Holevo bound on accessible information.Comment: 9 pages, revtex4. v2 corrects/adds some references and has a bit more discussio

    Romantic Love as a Spiritual Companionship? A Buddhist Re-Reading of George Eliot

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    Introduction Like most of George Eliot\u27s fiction, Daniel Deronda can be read as a story about the possibility of redemption. Gwendolen Harleth\u27 s vanity and ambition make her vulnerable to Grandcourt\u27 s desire for dominance, and their marriage is a disaster. Belatedly, Gwendolen comes to recognise that a marriage to Daniel Deronda instead of Grandcourt might have rescued her from her egotism and led to her moral and emotional salvation. But for Deronda finding a wife is part of exploring a wider social and spiritual significance for his existence - i.e. his Jewish cultural origin and the Zionist religious, historical, and political obligations he feels this entails. This stance towards his own life gives him a level of self-understanding that enables him to seek Mirah (who shares his general life aims) as his wife while responding to Gwendolen\u27s advances with supportive compassion. On the day of Deronda\u27s wedding to Mirah, he receives the following letter from Gwendolen: Do not think of me sorrowfully on your wedding day. I have remembered your words - that I may live to be one of the best of women, who make others glad that they were born. I do not yet see how that can be, but you know better than I. If ever it comes true, it will be because you helped me ... You must not grieve any more for me. It is better - it shall be better with me because I have known you. This is from the last pages of George Eliot\u27s published fiction. But whereas the study of Gwendolen\u27s downfall has been generally recognised as a masterpiece, the portrayal of Deronda as a redemptive hero has been greeted by many, if not most critics with scepticism. Leavis, writing in 1946, called it \u27unrealistic\u27, excessively \u27emotional\u27, and a failure of \u27creativity\u27 and \u27intelligence\u27. More analytically, in the 1990s, the problem of Deronda\u27s supposed implausibility has been related to the general failure of realism as a genre3 and to the failure of the ethic of universal sympathy: And in 1997 Rosemary Ashton is still \u27puzzled\u27: \u27Why does an agnostic ... set out without irony a religious ideal? Moreover, is the history of Judaism any less fraught with superstition, narrowness, exclusiveness than that of Christianity?\u27 This dichotomous response - admiration for George Eliot\u27s \u27realist\u27 observation of human weakness and disdain for her \u27idealistic\u27 fables of redemption - is not, of course, limited to Daniel Deronda. Henry James complained that all George Eliot\u27s novels are \u27moralized fables\u27 and are \u27only indirectly the products of observation\u27 and Leavis agrees with James that the moralized fable \u27gives us the unsatisfactory half\u27 of George Eliot.\u27 Consequently, for Leavis, not only is Daniel Deronda \u27a prig\u27 but Adam Bede\u27s love for Dinah is \u27merely charming\u27, Rufus Lyon is \u27a bore\u27, and the characterization of Maggie Tulliver is \u27immature\u27.8 And in 1982 Barbara Hardy writes of \u27the discontent which modem readers have felt with the complacency or simplicity of the idealistic strain\u27 in all her novels

    NLO QCD corrections to W+ W- b anti-b production with leptonic decays in the light of top quark mass and asymmetry measurements

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    We present the NLO QCD corrections to the processes p p and p anti-p to W+ W- b anti-b including leptonic decays of the W bosons. Non-resonant contributions as well as diagrams with doubly resonant and singly resonant top quark propagators are fully taken into account. We employ the narrow width approximation to perform the decays of the W bosons; spin correlations are however preserved. We also calculate observables relevant for top quark mass measurements, and study the impact of kinematical requirements and different scale choices on t anti-t asymmetries.Comment: 29 pages, 14 figures, version submitted to and accepted by JHE

    Appropriating the Returns from Industrial Research and Development

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    macroeconomics, industrial research and development, patent law
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