Galaxies in the local Universe fall into two main categories of spirals and ellipticals. In this Thesis, we explore the structural evolution of galaxies into this bimodal distribution.

Promotor: Koen Kuijken Co-promotor: Henk Hoekstra

The origin and evolution of galaxies are closely linked to many different physical phenomena.

Labbe

This thesis focuses on the X-ray spectral analysis of merging galaxy clusters and the plasma code development for future high-resolution X-ray spectroscopy observations.

Promotor: Prof.dr. H.J.A. Rottgering, Co-promotor: David Sobral

Galaxies are environments where gas coalesces, cools, and is converted into stars. However, it remains unclear the exact mechanisms through which galaxies acquire, redistribute and lose their gas.

The formation and evolution of galaxies is fundamentally driven by the formation of new stars out of cold gas.

Promotor: M. Franx, Co-Promotor: I.F. Labbé

This thesis investigates how galaxies form and what diversifies the evolutionary histories of galaxies.

This thesis explores the theoretical and observational properties of distant massive galaxies that harbour active black holes in their centres and shine brightly at radio wavelengths.

Promotor: H.J.A. Röttgering, Co-promotor: M. Haverkorn

Promotor: Prof.dr. M. Franx, Co-Promotor: Rychard Bouwens

Promotores: Prof.dr. J. Schaye & Prof.dr. C. Steidel (California Institute of Technology)

The thesis deals with the study of giant radio galaxies (GRGs), which are radio galaxies of megaparsec sizes.

Rossi

Franx

Of all the mass in our Universe, 80% is thought to consist of a hypothetical and invisible substance called dark matter (DM).

When observing star-forming galaxies, we are not only seeing stellar light, but we also see how this interacts with galactic gas and dust. This thesis contains studies of the stellar, nebular and dust properties of low mass star-forming galaxies.

Galaxies form and evolve through close interaction with their surroundings. As a result, the heavy elements ('metals') that are synthesized in stars, are found both inside and outside galaxies.

Promotores: Prof.dr. M. Franx, Prof.dr. M. Kriek (Univ. of California at Berkeley)

Researchers at Leiden Observatory study the fundamental physics that creates structure in the Universe. These processes collect matter into galaxies and gas into stars. With the use of powerful telescopes and advanced calculations and computer simulations, Leiden astronomers seek to understand the origin,…

Researchers at Leiden Observatory study the fundamental physics that creates structure in the Universe. These processes collect matter into galaxies and gas into stars. With the use of powerful telescopes and advanced calculations and computer simulations, Leiden astronomers seek to understand the origin,…

Galaxies form and live inside dark matter haloes. As a consequence, they are exposed to the tidal fields generated by the surrounding matter distribution: this imprints a preferential direction to the galaxy shapes, which leads to a coherent alignment on physically close galaxies, called intrinsic a…

Promotores: Prof.dr. F.P. Israel, Prof.dr. P.P. van der Werf

In this thesis, the research focuses on the properties of dark matter and dark matter haloes and how they connect with the galaxies we can observe in the Universe.

Promotor: J. Schaye

Promotores: Prof.dr. J. Schaye, Prof.dr. S.D.M. White (MPA Garching)

Promotores: Prof.dr. M. Franx & Prof.dr. P.G. van Dokkum (Yale University)

How did galaxies form? How did galaxies evolve?

In this thesis, I studied the origin and evolution of the non-thermal radiation in merging galaxy clusters.

The intracluster medium (ICM) is a hot, tenuous and X-ray emitting gas that pervades galaxy clusters.

Promotor: Prof.dr. K.H. Kuijken, Co-Promotor: Dr. H.Hoekstra

We investigate the buildup of galaxies from various vantage points. The first two chapters focus on the stellar content of galaxies, especially the distribution of stellar masses at birth and potential variations therein in various galactic environments.

Galaxy intrinsic alignments induce a major astrophysical contamination to weak gravitational lensing measurements and need to be modelled and mitigated when extracting cosmological information from such measurements.

This thesis investigates the structural evolution and assembly of galaxies since the first few billions years after the big bang.

Promotor: F.P. Israel, Co-Promoter: R. Meijerink

Dwarf satellite galaxies in the Milky Way perform different dances than researchers initially expected. Marius Cautun from Durham University received a Marie Curie grant to unravel the mysteries of this orbital dance. October 1st 2018 he will start his research at the Leiden Observatory.

Promotor: H.J.A. Röttgering, Co-promotor: G.K. Miley

Promotor: Prof.dr. S.F. Portegies Zwart, Co-promotor: D.C. Heggie

Unfolding potential

In this thesis, I study the formation of large-scale structure and the physics of particle acceleration at large scales (~Mpc).

In the thesis the dynamics of strategies is studied from two perspectives.In the first part of the thesis strategies are considered to be opinions present in a community.

This thesis aims to enhance our understanding of galaxies by testing theoretical models of galaxy formation against observations, particularly in the cases of extreme systems which have been found to have an excess of baryonic mass in their central regions, in the form of either supermassive black holes…

In this thesis, dynamic testing principles were applied to examine young children's potential for learning. Our studies focused on the role of cognitive flexibility, to further increase our understanding of the cognitive processes involved in children's ability to learn from instruction and feedback,…

Promotor: Jelle S. Kaastra Co-promotor: Jelle de Plaa

An assessment approach that tailors to children’s instructional needs

Can dynamic testing provide us with insight in children’s potential for learning?

The solar system was formed approximately 4.56 billion years ago. Despite the numerous theories that have been developed over the years, the formation and evolution of the solar system still remain unclear.