1,039 research outputs found

    Dynamic collective theory of odd-a nuclei

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    The unified model and the collective giant-dipole-resonance model are unified. The resulting energy spectrum and the transition probabilities are derived. A new approximate selection rule involving the symmetry of the γ vibrations is established. It is verified that the main observable features in the photon-absorption cross section are not influenced by the odd particle, despite the considerably richer spectrum of states as compared to even-even nuclei

    Static theory of the giant quadrupole resonance in deformed nuclei

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    The modes and frequencies of the giant quadrupole resonance of heavy deformed nuclei have been calculated. The quadrupole operator is computed and the absorption cross section is derived. The quadrupole sum rule is discussed, and the relevant oscillator strengths have been evaluated for various orientations of the nucleus. The giant quadrupole resonances have energies between 20 and 25 MeV. The total absorption cross section is about 20% of the giant dipole absorption cross section. Of particular interest is the occurrence of the quadrupole mode which is sensitive to the nuclear radius in a direction of approximately θ=(1/4)π from the symmetry axis. This may give information on the details of the nuclear shape

    Poisson problems for semilinear Brinkman systems on Lipschitz domains in Rn

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    The purpose of this paper is to combine a layer potential analysis with the Schauder fixed point theorem to show the existence of solutions of the Poisson problem for a semilinear Brinkman system on bounded Lipschitz domains in Rn (n 65 2) with Dirichlet or Robin boundary conditions and data in L2-based Sobolev spaces. We also obtain an existence and uniqueness result for the Dirichlet problem for a special semilinear elliptic system, called the Darcy\u2013Forchheimer\u2013 Brinkman system

    Loewner PDE in infinite dimensions

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    In this paper, we prove the existence and uniqueness of the solution f(z,t)f(z,t) of the Loewner PDE with normalization Df(0,t)=etADf(0,t)=e^{tA}, where A∈L(X,X)A\in L(X,X) is such that k+(A)<2m(A)k_+(A)<2m(A), on the unit ball of a separable reflexive complex Banach space XX. We also give improvements of the results obtained recently by Hamada and Kohr, but we omit their proofs for the sake of brevity. In particular, we obtain the biholomorphicity of the univalent Schwarz mappings v(z,s,t)v(z,s,t) with normalization Dv(0,s,t)=e−(t−s)ADv(0,s,t)=e^{-(t-s)A} for t≥s≥0t\geq s\geq 0, where m(A)>0m(A)>0, which satisfy the semigroup property on the unit ball of a complex Banach space XX. We further obtain the biholomorphicity of AA-normalized univalent subordination chains under some normality condition on the unit ball of a reflexive complex Banach space XX. We prove the existence of the biholomorphic solutions f(z,t)f(z,t) of the Loewner PDE with normalization Df(0,t)=etADf(0,t)=e^{tA} on the unit ball of a separable reflexive complex Banach space XX. The results obtained in this paper give some positive answers to the open problems and conjectures proposed by the authors in 2013

    Nursing home patients\u27 perception of control over their environment

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    High Resolution Ozone Mapper (HROM)

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    Using the backscatter ultraviolet instrument (BUV) aboard NIMBUS 4 as a baseline, point scanner mechanisms and spatial multiplex scanning systems were compared on the basis of sensitivity, field of view and simplicity. This comparison included both spectral and spatial scanning and multiplexing techniques. The selected system which optimally met the performance requirements for a shuttle based instrument was a pushbroom spatial scanner using a 15 element photomultiplier tube array and a Hadamard multiplex spectral scan. The selected system was conceptually designed. This design includes ray traces of the monochromator, mechanical layouts and the electronic block diagram
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