Sökning: "white dwarfs"
Visar resultat 6 - 10 av 10 avhandlingar innehållade orden white dwarfs.
6. Spectral Properties of Type Ia Supernovae and Implications for Cosmology
Sammanfattning : Type Ia supernovae can, for a short period of time, reach the same brightness as an entire galaxy. They are responsible for the creation of a large fraction of all heavy elements and can be used, as standard candles, to prove that the expansion of the universe is accelerating. Yet, we do not fully understand them. LÄS MER
7. 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
8. Dynamical atmospheres and winds of M-type AGB stars
Sammanfattning : Mass loss, in the form of slow stellar winds, is a decisive factor for the evolution of cool luminous giants, eventually turning them into white dwarfs. These dense outflows are also a key factor in the enrichment of the interstellar medium with newly produced elements from the interior of these stars. LÄS MER
9. Fronts and instabilities in laser ablation, organic semiconductors and quantum media
Sammanfattning : The concept of a front plays a decisive role in various elds in physics and beyond. In the present thesis we study key aspects of front dynamics and stability in the context of laser plasmas, organic semiconductors and quantum media. LÄS MER
10. Waves and instabilities through the lens of asymptotic analysis
Sammanfattning : Understanding the interaction of water waves with winds and marine currents is a fundamental problem in geophysical fluid dynamics. From the point of view of hydrodynamic stability, surface waves are regarded as perturbations of an inviscid parallel shear flow modeling the wind in the air and the current in the water. LÄS MER