Sökning: "relativistic particles"
Visar resultat 16 - 20 av 38 avhandlingar innehållade orden relativistic particles.
16. Generation of magnetic fields in plasmas
Sammanfattning : Relativistic and non-relativistic plasma outflows are quite ubiquitous in astrophysical scenarios, as well as in laboratory plasmas. The propagation of relativistic and non- relativistic charged particle beams in background plasmas provides return currents in the opposite direction and interactions between the currents then drive several plasma instabilities involving the longitudinal (electrostatic instabilities) and trans- verse (electromagnetic instability) modes. LÄS MER
17. Cosmological models, nonideal fluids and viscous forces in general relativity
Sammanfattning : This thesis addresses the open questions of providing a cosmological model describing an accelerated expanding Universe without violating the energy conditions or a model that contributes to the physical interpretation of the dark energy. The former case is analyzed considering a closed model based on a regular lattice of black holes using the Einstein equation in vacuum. LÄS MER
18. Modelling of laser plasma interaction with applications to particle acceleration and radiation generation
Sammanfattning : The development of laser systems with ultra-high intensities has allowed the study of the relativistic interaction of laser light and ionized matter, plasmas, as well as opened up prospects for compact particle accelerators, generation of high intensity X-ray, XUV radiation, and probing QED-effects, which are present in the high intensity regime. To describe laser matter interaction, it is necessary to self-consistently account for the paths of a large number of particles and the corresponding electromagnetic fields, with the addition of stochastic effects at high laser intensities. LÄS MER
19. Modelling of laser plasma interaction with applications
Sammanfattning : The development of laser systems with ultra-high intensities has both opened up prospects for compact particle accelerators, as well as probing QED-effects, which are present in the high intensity regime. To describe laser matter interaction, it is necessary to self-consistently account for the paths of a large number of particles and the corresponding electromagnetic fields, with the addition of stochastic effects at high laser intensities. LÄS MER
20. Pushing methods for plasma simulations into the QED regime
Sammanfattning : The interaction between a super-intense laser pulse, with intensity up to 10²² W/cm², and a plasma opens new regimes of physics, with new questions and more demand on existing numerical tools. Relativistic and quantum effects which are negligible for lower laser intensities become important and must be properly modelled to generate reliable predictions. LÄS MER