Sökning: "Scattering resonances"

Visar resultat 1 - 5 av 45 avhandlingar innehållade orden Scattering resonances.

  1. 1. Resonances of Dirac Operators

    Författare :Jimmy Kungsman; Wolfgang Staubach; Roman Schubert; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Semiclassical analysis; Dirac operator; resonances; Poisson trace formula; scattering theory; complex absorbing potential; pseudodifferential operator; Mathematics; Matematik;

    Sammanfattning : This thesis consists of a summary of four papers dealing with resonances of Dirac operators on Euclidean 3-space. In Paper I we show that the Complex Absorbing Potential (CAP) method is valid in the semiclassical limit for resonances sufficiently close to the real line if the potential is smooth and compactly supported. LÄS MER

  3. 2. Ways of determining and characterising resonances in scattering processes

    Författare :Ksenia Shilyaeva; Nils Elander; Dage Sundholm; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum scattering theory; complex scaling; resonances; Molecular physics; Molekylfysik; fysik; Physics;

    Sammanfattning : Scattering cross sections very often display structures. To clarify if these structures correspond to resonances one has to check if they are poles of the scattering matrix (S-matrix) in the fourth quadrant of the complex momentum plane. Furthermore, the states corresponding to these poles also need to have an appropriate scattering amplitude. LÄS MER

  4. 3. Inverse scattering and distribution of resonances on the real line

    Författare :Michael Hitrik; Matematik LTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematics; scattering poles; reflection coefficient; Schrödinger operator; inverse scattering; Matematik;

    Sammanfattning : We study aspects of scattering theory for the Schrödinger operator on the real line. In the first part of the thesis we consider potentials supported by a half-line, and we are interested in the inverse problem of reconstruction of the potential from the knowledge of values of the reflection coefficient at equidistributed points on the positive imaginary axis. LÄS MER

  5. 4. Reliable hp finite element computations of scattering resonances in nano optics

    Författare :Juan Carlos Araujo-Cabarcas; Christian Engström; David Cohen; Mats G. Larson; Jeffrey Ovall; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Scattering resonances; Helmholtz problems; pseudospectrum; Lippmann-Schwinger equation; finite element methods; nonlinear eigenvalue problems; spurious solutions;

    Sammanfattning : Eigenfrequencies are commonly studied in wave propagation problems, as they are important in the analysis of closed cavities such as a microwave oven. For open systems, energy leaks into infinity and therefore scattering resonances are used instead of eigenfrequencies. LÄS MER

  7. 5. Bound states and resonances in three-body system

    Författare :Yarevsky Evgeny; Thomas N. Rescigno; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Three-body problem; Total angular momentum representation; Resonances; Complex Scaling Method; Finite Element Method; Eigenvalues problem.; Physics; fysik;

    Sammanfattning : The quantum three-body problem plays an important role in different branches of the modern physics. In the nuclear, atomic and molecular physics there exist a number of systems whose behaviour is naturally described in this framework. LÄS MER