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Stellar streams are made of stars that originate from globular clusters or dwarf satellite galaxies that have been disturbed by the gravitational pull from the galaxy they orbit. These stellar streams hold information about the history of the progenitor as well as information about the gravitational potential of the host galaxy. In this thesis we make use of the high resolution cosmological zoom s
In this thesis, I investigate if the binaries that are being tidally disrupted by means of the Hills mechanism, producing hypervelocity stars, could have been transported to the galactic centre by two-body scattering. To survive a scattering event, the binary must be hard, meaning that the binding energy of the binary is higher than the kinetic energy of the collider. If the binary is soft, the bi
Two relatively new concepts in planetary science are planetary migration; wherein the planets migrate through the protoplanetary disk as they form, and pebble accretion; wherein the planetesimals which become terrestrial planets and giant planet cores grow through the accretion of small pebbles. Planetary migration has become a generally accepted concept but there is still much to be learned even
The evolution of globular star clusters tells the history of the formation of galaxies, how stellar streams might have formed and how the future of the Universe might look like. Although the general theoretical background of the evolution is well understood, it is difficult to conduct accurate and realistic computer simulations of objects containing thousands of interacting bodies. This project in
What effect does a collision between two clusters have on their dissolving time? In order to answer this question, a new type of N-body simulation using a double integration of a cluster was built. Instead of introducing a perturbation representing the gravitational force of the Milky Way into a local simulation of the cluster, the cluster orbit was integrated in the potential of the Milky Way,
Context. The planet-metallicity correlation for gaseous giants is widely accepted through spectroscopic studies. However, whether a similar correlation exists for terrestrial planets is a debated subject. High-precision spectroscopic abundance analysis on Sun-like stars suggested that the Sun is depleted in refractory elements with respect to its solar twins without exoplanets, likely due to the f
In recent years, scientists have found unconfirmed evidence for a ninth planet in the solar system at a very wide orbit. The parameters for this planet are poorly constrained. Current estimates mostly come from the effect the planet has on trans-neptunian objects. Here we investigate an alternative scenario, that is whether this proposed planet can exert observable perturbation on Main Belt astero
Orbital or mean motion resonance (MMR) occurs when the orbital period ratio between two planets is close to a ratio of small integers. MMR can protect planets from collisions and affects the overall final architecture of the system. Observations of exoplanets have shown that the survival rate of MMR-chains is low, and most systems are near and just wide of an exact MMR. The most common chains are
Blue stragglers were first discovered as hotter and more luminous than the turnoff in the globular cluster M3. Their presence is typically explained by the interplay between stellar collisions and mass transfer in binary systems. In this thesis, I study blue stragglers produced from primordial binary evolution. This is done by both reproducing individual blue stragglers, to examine the different f
Galaxies contain a wide variety of star clusters with different properties. Each cluster is a possible source of runaway stars, which can be progenitors of supernovae in other parts of the galaxy than their home cluster. Considering runaway stars in galaxy simulations has shown to increase the galactic feedback. This project investigates how the initial condition of a star cluster affects the velo
Satellite galaxies on bound orbits around the Milky Way (MW) are constantly subject to tidal forces from the MW. If the tidal forces are large enough, they may strip the outermost stars of the satellite, that in turn distribute themselves in long elongated stellar streams. These stellar streams are good probes of the Galactic potential due to the constraints they place on the structure of the pote
Since 2015, the LIGO-Virgo-KAGRA scientific collaboration (LVK) has detected gravitational waves from more than 90 merging compact object binaries using ground-based interferometric detectors. Compact objects orbiting in binary systems emit gravitational waves leading to a loss of energy. This results in the decay of the orbit leading to the merger of these inspiralling objects. Around 83 of the m
Using methods of smoothed particle hydrodynamics (SPH) an N -body simulation was set-up to investigate stellar encounters between a 1 solar-mass main sequence (MS) star, modeled after the Sun, and a 0.6 solar-mass white dwarf (WD). This was done primarily to investigate the assumptions made by Mastrobuono-Battisti et al. (2021) in search of the impact of stellar encounters on stellar population in
We probe the implications of 5 different previously developed models of the evolution of the Milky Way’s radial metallicity gradient for radial migration of stars observed today between 5kpc < R < 12kpc. Our sample contains 7167 giant stars, with metallicities and radial velocities obtained from APOGEE DR14, full 5-parameter kinematic information from Gaia DR2, and ages derived in Martig et al. 20
A star forms with a surrounding protoplanetary disk after the collapse of a molecular cloud core. Subsequently, over a period of several Myr this protoplanetary disk of dust and gas is accreted onto the host star. We model the formation and evolution of such a protoplanetary disk using a one-dimensional numerical model. We find that disks form on a time scale of less than 1 Myr and that the size a
The consensus in the field is that we have a pretty good understanding of the physics behind star formation and evolution. So far, the models that have been created characterize the different collections of stars in our Milky Way galaxy with decent accuracy, and they have allowed for humanity to obtain insights into how our universe evolved. However, the author believes that our current techniques
The observations of circumbinary planets have confirmed that these can in fact be stable. While previous studies on circumbinary planets have been done, not many have been made on systems containing multiple circumbinary planets on eccentric orbits. In this thesis, the effects a binary star system of solar mass would have on the Solar System is investigated. Using the program MERCURY, numerous int
Short gamma-ray bursts are often observed at large spatial offsets from their host galaxies. Neutron star mergers in double neutron star binaries have also recently been confirmed as a progenitor of short gamma-ray bursts (Abbott et al. 2017). We attempt to constrain uncertainties in the evolution of burst-producing neutron star binaries by generating a distribution of burst offsets from the neutr
