Sökning: "accretion"

Visar resultat 31 - 35 av 63 uppsatser innehållade ordet accretion.

1. 31. Investigating super-Eddington accretion flows in Ultraluminous X-ray sources

   Master-uppsats, Luleå tekniska universitet/Rymdteknik

   Författare :Andrés Gúrpide Lasheras; [2018]
   Nyckelord :Accretion; X-ray binaries; Black holes; Neutron Stars; Ultraluminous X-ray sources;

   Sammanfattning : It is now widely known that most of the large galaxies we observe (e.g. the Milky Way) host in their center a supermassive black hole ($10^{6}-10^{9}$ $M_\odot$). LÄS MER

3. 32. Planet migration in evolving protoplanetary discs

   Master-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation; Lunds universitet/Institutionen för astronomi och teoretisk fysik - Genomgår omorganisation

   Författare :Linn Eriksson; [2018]
   Nyckelord :Planets and satellites: formation; Protoplanetary discs: evolution; Planet-disc interactions; Physics and Astronomy;

   Sammanfattning : The rate of migration and accretion onto protoplanets is greatly influenced by the structure of the surrounding protoplanetary disc. This structure changes with time as the disc evolves on a million year timescale, implying that the process of planet formation might look very different depending on when it was initiated. LÄS MER

4. 33. Nucleosynthesis in accretion disks around black holes

   Master-uppsats, Lunds universitet/Institutionen för astronomi och teoretisk fysik - Genomgår omorganisation; Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Neige Frankel; [2017]
   Nyckelord :accretion disk; Nucleosynthesis; black hole; high energy; white dwarf tidal disruption; Physics and Astronomy;

   Sammanfattning : Nucleosynthesis is the mechanism which produces new elements in nuclear reactions. Nuclear reaction rates are highly temperature dependant, and nuclear reactions take place in very hot environments. Current theories predict that the light elements such as hydrogen and helium were produced during the Big Bang. LÄS MER

5. 34. Can planet formation explain the observed differences in the chemical composition of binary stars?

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Rebecca Forsberg; [2017]
   Nyckelord :binary stars; planet formation; protoplanetary disc; Physics and Astronomy;

   Sammanfattning : A suggested explanation for the observed differences in chemical abundances in binary stars has been planet formation (e.g. Tucci Maia et al. 2014). LÄS MER

7. 35. High energy gamma ray emission and multi-wavelength view of the AGN PKS 0537-441

   Kandidat-uppsats, Linnéuniversitetet/Institutionen för fysik och elektroteknik (IFE); Linnéuniversitetet/Institutionen för datavetenskap (DV)

   Författare :Emma Fransson; [2017]
   Nyckelord :astrophysics; AGN; PKS 0537-441; jet; accretion; synchrotron self compton; spectral energy distribution;

   Sammanfattning : This thesis describes the analysis of Very High Energy (VHE) emission from the Active Galactic Nucleus PKS 0537-441. It also aims to put the results in a wider context by implementing previous work done on this source. The data chosen for the analysis is provided by the Fermi-LAT satellite and covers the energy range between 300 MeV and 300 GeV. LÄS MER