Sökning: "scattering poles"

Hittade 5 avhandlingar innehållade orden scattering poles.

  1. 1. Inverse scattering and distribution of resonances on the real line

    Detta är en avhandling från Department of Mathematics, Lund University

    Författare :Michael Hitrik; Lunds universitet.; Lund University.; [1998]
    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

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

    Detta är en avhandling från Stockholm : Department of Physics, Stockholm University

    Författare :Ksenia Shilyaeva; Stockholms universitet.; [2009]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum scattering theory; complex scaling; resonances; NATURAL SCIENCES Physics Atomic and molecular physics Molecular physics; NATURVETENSKAP Fysik Atom- och molekylfysik 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

  3. 3. Elastic Wave Scattering by Closed Cracks and Thin Flaws - Multiple Scattering and Resonances

    Detta är en avhandling från Chalmers University of Technology

    Författare :Arne S. Eriksson; Chalmers tekniska högskola.; Chalmers University of Technology.; [1992]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Teknisk mekanik; Engineering mechanics; ultrasonic testing; evaluation of materials; SH-wave; direct integral equation; singularity expansion;

    Sammanfattning : In this thesis we study elastic wave scattering by thin flaws and closed cracks, which finds applications in ultrasonic testing and evaluation of materials. First we consider the scattering of an SH-wave by a thin finite elastic layer between two elastic half-spaces. LÄS MER

  4. 4. Analysis of Planar and Circular Cylindrical Multilayer Structures with Application to Soft and Hard Surfaces

    Detta är en avhandling från Chalmers University of Technology

    Författare :Zvonimir Sipus; Chalmers tekniska högskola.; Chalmers University of Technology.; [1997]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Elektroteknik; elektronik och fotonik; Electrical engineering; electronics and photonics; antennas; approximate boundary conditions; corrugated surfaces; EFIE; Green s functions; group representation theory; integral equations; microstrip antennas; moment method; multilayer structures; periodic metal strips; periodic surfaces; soft and hard surfaces; spectral domain analysis; strip scatterers;

    Sammanfattning : This thesis deals with the analysis of planar and circular cylindrical multilayer structures, such as strip-loaded dielectric layers, corrugated surfaces and microstrip antennas. In particular, we study corrugations and strip-loaded grounded dielectric slabs when they are used to realize soft and hard surfaces. LÄS MER

  5. 5. Effective Field Theory for QCD-like Theories and Constraints on the Two Higgs Doublet Model

    Detta är en avhandling från Department of Astronomy and Theoretical Physics, Lund University

    Författare :Jie Lu; Lunds universitet.; Lund University.; [2011]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; QCD-like; effective field theory; symmetry breaking; renormalization group; two Higgs doublet model;

    Sammanfattning : Abstract in Undetermined This thesis includes two topics. The first three papers is the major part of this thesis, which is about higher order calculations in the effective field theories of three QCD-like theories. These three QCD-like theories are distinguished by having quarks in a complex, real or pseudo-real representation of gauge group. LÄS MER