Browsing Fakultät für Physik (inkl. GAUSS) by Title
Now showing items 1-20 of 952
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3-D Modeling of Coronal Mass Ejections with STEREO/SECCHI Data
(2017-02-28)This thesis reports on the three-dimensional analysis of coronal mass ejections (CMEs) in order to answer questions about their morphology and to derive their three-dimensional geometry. The questions are about the ... -
3D STED Microscopy with Pulsed and Continuous Wave Lasers
(2008-04-16)STED microscopy improves the resolution of fluorescence microscope by effectively quenching the population of the excited state in the outer regions of the focus. The resolution capability in STED microscopy has already ... -
3d virtual histology of neuronal tissue by propagation-based x-ray phase-contrast tomography
(2018-07-05)Deciphering the three-dimensional (3d) cytoarchitecture of neuronal tissue is an important step towards understanding the connection between tissue function and structure and determining relevant changes in neurodegenerative ... -
A Characterization Theorem for Local Operators in Factorizing Scattering Models
(2013-01-10)In quantum field theory, the rigorous construction of local observables in the presence of nontrivial interaction is a crucial problem. In a class of integrable quantum field theories, a very abstract existence proof ... -
A coronal loop in a box: From energy generation to coronal emission
(2023-03-17)The corona is the outer atmosphere of the Sun. It contains an abundance of bright arcs that consist of hot plasma trapped by the magnetic field. These coronal loops are heated to temperatures far surpassing the solar surface ... -
A Dedicated Endstation for Waveguide-based X-Ray Imaging
(2012-08-30)X-ray microscopy has emerged as a powerful and versatile imaging technique in many fields of science over the last years, offering insights in opaque media at high spatial resolution. A major challenge remains the ... -
A feasibility study about the use of vector tomography for the reconstruction of the coronal magnetic field
(2006-03-20)The magnetic field contains the dominant energy per unit volume in the solar corona and therefore plays an important role in most coronal phenomena. But until now, no direct measurement of ... -
A matter of brightness: table-top X-ray generation inside waveguides and X-ray holography with single free-electron laser pulses
(2022-03-22)X-ray microscopy delivers insights into the structure of optically opaque bulk specimens with high spatial resolution. The source brightness poses a limit on the achievable resolution, however. While table-top X-ray sources ... -
A novel approach of immittance-spectra analysis and how it resolves a decade-old deviation of the Frenkel-Poole model
(2017-02-23)Immittance (i.e. a generalisation of all quantities containing identical information as e.g. the impedance) spectroscopy is a well-established and versatile method with a broad range of applications in a wide variety of ... -
A search for the Rieger-type periodicity on the Sun- like stars
(2023-10-06)Solar activity undergoes variations over many different timescales. The main periodicity is 11 years, called Schwabe cycle. In addition to the 11-year cycle, shorter periodic variations known as Rieger cycles have been ... -
A semi-microscopic model of synaptic transmission and plasticity
(2000-08-28)A stochastic model of synaptic transmission has been designed on the basis of electro-physiological experiments. Monte Carlo simulations are performed which include presynaptic mechanisms ... -
A Top Quark Mass Measurement Using the R32 Stabilized Variable with the ATLAS Detector
(2012-08-31)This thesis presents one of the first measurements of the top quark mass at the ATLAS experiment, one of the four large experiments located along the LHC. First discovered in 1995 at the Tevatron experiments CDF and D0, ... -
A Unitary Perturbation Theory Approach to Real-Time Evolution in the Hubbard Model
(2019-10-29)We advance perturbative approaches for out-of-equilibrium quantum many-body systems by applying unitary perturbation theory to the real-time evolution of the weakly interacting Hubbard model in d > 1 dimensions. We derive ... -
A Variational Cluster Approximation for the Heisenberg Model
(2017-04-13)In this thesis we present a novel variational cluster approximation for Heisenberg spin systems. It is based on the self-energy functional theory by Potthoff for fermionic and bosonic models with local interactions. To ... -
A waveguide-based lens-less x-ray microscope
(2006-09-05)A lot of effort is currently invested to realize phase contrast imaging with hard x-rays. For specimen consisting of light elements, e.g. biological samples, the induced phase shift of the ... -
Ab-initio Studies of X-ray Scattering
(2010-07-15)As the emergence of the FEL sources opens up new opportunities in material research, the theory and modeling of the behavior of matter in strong x-ray laser fields, as well as novel approaches ... -
Actin Filaments and Bundles in Flow
(2008-08-06)Actin, a protein and major component of the cytoskeleton, is organized in vivo into filaments, bundles, and networks which play an important role in mechanical stability and cellular motility. ... -
Actin structure formation, membrane dynamics, and force generation during blood platelet spreading
(2023-03-17)Blood platelets are essential to the formation of blood clots and prevent uncontrolled bleeding. They are non-nucleated fragments of larger bone marrow cells known as megakaryocytes. Platelets undergo fast morphological ... -
Active cancellation of 3D Tollmien-Schlichting waves in the presence of sound and vibrations.
(2002-12-13)In order to delay the laminar-turbulent transition in a boundary layer flow, the cancellation of 2D- and 3D instability waves by artificially excited counter-disturbances is investigated. ... -
Active Emulsions: Physicochemical Hydrodynamics and Collective Behavior
(2021-07-02)Active matter is a collection of constituent elements that constantly consume energy, convert it to mechanical work, and interact with their counterparts. These materials operate out of equilibrium and exhibit fascinating ...