Hae
Aineistot 1-10 / 12
Observational studies of accreting X-ray pulsars in a broad energy range
(Turun yliopisto, 2022-11-04)
Among all interesting astrophysical objects in the universe, only a few are capable of improving our understanding of physics under extreme conditions. Accreting neutronstars are one of these objects. These compact objects ...
High-precision polarimetric, broad-band spectroscopic and temporal studies of black hole X-ray binaries
(Turun yliopisto, 2021-10-08)
Black holes are among the most unusual objects in the Universe. Powered through accretion, they are strong sources of radiation in a broad energy range, from radio to hard X-rays. Stellar-mass black holes manifest themselves ...
Where Are the Stars of Yesteryear?: A Reflection on Astrophysical Transience
(Turun yliopisto, 2025-02-24)
This thesis concerns a number of kinds of astrophysical transients, including interacting supernovae (SNe), gap transients and tidal-disruption events. There are three papers included and they address differing phenomena, ...
Mass and radius constraints for neutron stars using X-ray timing, spectral, and polarization observations
(Turun yliopisto, 2020-12-11)
Neutron stars (NSs) are the most dense objects in the Universe that can be directly observed. The nature of the cold ultra-dense matter inside them is still unresolved, and determining the equation of state (EoS) of that ...
Environments of Active Galaxies
(Turun yliopistoAnnales Universitatis Turkuensis A I 447, 2012-11-10)
This dissertation presents studies on the environments of active galaxies.
Paper I is a case study of a cluster of galaxies containing BL Lac object RGB
1745+398. We measured the velocity dispersion, mass, and richness ...
Bl lac objects - view from the highest energies
(Turun yliopisto, 2020-06-16)
Relativistic jets launched by a super-massive black holes are among the most extreme particle accelerators in the Universe. BL Lac objects host a relativistic jet that points very close to our line of sight. They are the ...
Properties of highly magnetized neutron stars from X-ray timing analysis on different time scales
(Turun yliopisto, 2022-10-26)
Massive stars end their lives either by collapsing directly into a black hole or by exploding as a supernova, leaving behind their collapsed core, a black hole or a neutron star (NS). NSs are a showcase of extremities: ...
Analytical techniques for X-ray polarization studies of rapidly rotating neutron stars and black holes
(Turun yliopisto, 2025-05-23)
Compact stellar remnants such as neutron stars and black holes attract not only mate¬rial from their surroundings but also the close attention of astronomers. The latter is because these objects constitute unattainable ...
Galaxy evolution through the lens of active galactic nuclei, their host galaxies, and environments
(Turun yliopisto, 2024-06-11)
The body of research relayed in this dissertation pertains to investigating the immediate environments of Type I quasars for clues to the formation and evolution of galaxies through observations. The neighboring galaxies ...
X-ray bursts as a tool to constrain the equation of state of the ultra-dense matter inside neutron stars
(Turun yliopisto, 2017-12-15)
Neutron stars are one of the most dense objects in the Universe. However, the exact description of the equation of state (EoS) of the cold ultra-dense matter inside them is still a mystery. In this thesis, we measure the ...