Sökning: "Stephan Rosswog"
Hittade 5 avhandlingar innehållade orden Stephan Rosswog.
1. Attraction and Rejection : On the love–hate relationship between stars and black holes
Sammanfattning : Solitary stars wandering too close to the supermassive black hole at the centre of their galaxy may become tidally disrupted, if the tidal forces due to the black hole overcome the self-gravity holding the star together. Depending on the strength of the encounter, the star may be partially disrupted, resulting in a surviving stellar core and two tidal arms, or may be completely disrupted, resulting in a long and thin tidal stream expected to fall back and circularize into an accretion disc (the two cases are illustrated on the cover of this thesis). LÄS MER
2. The Advanced Spectral Leakage (ASL) scheme for simulations of merging neutron stars
Sammanfattning : The detection of a blue macronova following the event GW170817 has emphasized the role that neutrinos play in merging neutron stars. In particular, neutrinos are able to drive mass ejection, the so-called neutrino-driven winds, and change the neutron richness of the matter by absorption. LÄS MER
3. Photospheric emission in gamma-ray bursts
Sammanfattning : This thesis considers emission from gamma-ray bursts (GRBs), the most powerful explosions known in the Universe. Most GRBs are likely associated with the final stages of stellar evolution, where the core of a massive star collapses, and gives birth to a highly compact object such as a neutron star or black hole. LÄS MER
4. Jet-Ejecta Interactions in Neutron Star Mergers : How jets interacting with the surroundings affect multi-wavelength observations
Sammanfattning : In August 2017 a gravitational wave signal from a binary neutron star merger was detected for the first time, and it was followed by several electromagnetic detections that spanned the whole electromagnetic spectrum. Those observations proved the ejection of two dynamical components: mildly-relativistic neutron rich ejecta and an ultra-relativistic jet. LÄS MER
5. Jet-wind interaction in neutron star mergers
Sammanfattning : Besides being sources of gravitational waves, there has been evidence that neutron starmergers release neutron-rich material suitable for the production of heavy r-process nuclei.The radioactive decay of these freshly synthesised elements powers a rapidly evolvingthermal transient, the “macronova” (also known as “kilonova”). LÄS MER
