Promotor: Prof.dr. E.F. van Dishoeck, Co-Promotor: M.R. Hogerheijde

Multiple stars, that is two or more stars composing a gravitationally bound system, are common in the universe.

One of the key quests in astronomy is to study the growth and evolution of galaxies across cosmic time. Radio observations provide a powerful means of studying the formation of stars and subsequent buildup of distant galaxies, in a way that is unbiased by the presence of dust.

Promotor: Prof.dr. E.F. van Dishoeck

The origin and evolution of galaxies are closely tied to the cyclic feedback processes between stars and the interstellar medium (ISM).

Wetenschappers bij de Leidse Sterrewacht onderzoeken de oorsprong van sterren en hun planetenstelsels. Ze detecteren en karakteriseren planeten rondom andere sterren (exoplaneten). Ze onderzoeken hoe sterren en planeten ontstaan. En ze volgen moleculen van interstellaire wolken tot planetenstelsels…

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

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

Promotor: Prof.dr. E.F. van Dishoeck, Prof.dr. F.F.S. van der Tak (RUG)

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.

OB associations are loose groups of young, massive stars. They constitute the last stage of the massive starformation process, and the context in which new stars are formed.

To address the fundamental questions of how life on Earth emerged and how common life may be in the Universe, it is crucial to know the chemical composition of the planet-forming material.

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

The focus of this thesis is how stars like our Sun and planets like Jupiter, Saturn, and Earth are formed.

Promotor: Prof.dr. E. F. van Dishoeck

Sobral

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

Promotor: J. Schaye

This thesis discusses the physical and chemical processes than influence the composition of forming planets.

We have conducted a full spectral line survey of the 3-13 micron region of two massive protostars, AFGL 2591 and AFGL 2136, for the first time at high spectral resolution.

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

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

Promotor: Prof. dr. A.G.G.M. Tielens

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

The work presented in this thesis is based on ALMA surveys of protoplanetary disks in three star-forming regions: Lupus, OMC-2, and NGC 2024.

The high velocity tail of the total velocity distribution of stars provides essential insight into fundamental properties of the Galaxy.

Promotor: Prof.dr. A.G.G.M. Tielens

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.

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…

Promotores: Prof.dr. A.G.G.M. Tielens, Prof.dr. L. Kaper (UvA)

Circumstellar discs are the reservoirs of gas and dust that surround young stars and have the potential to become planetary systems.

Promotor: P. T. de Zeeuw, Co-promotor: N. Neumayer; G. van de Ven

Op 25 september 2022 gaat er in Leiden een bijzonder experiment plaatsvinden: Seeing Stars Leiden. In de wijde omgeving van de Leidse Oude Sterrewacht gaan een uur lang alle lichten uit.

Promotor: Roeland M.H. Merks

Large areas of space are filled by molecular clouds that consist of gas and dust grains that are the remnants of dead stars. When these clouds start collapsing, the decreasing temperature and increasing density cause gas particles to start accreting onto dust grain surfaces.

This thesis develops a method for direction dependent calibration of the ionosphere in radio interferometric data.

Promotor: Prof.dr. E.F. van Dishoeck, Co-Promotor: G.J. Herczeg

Promotor: G.P. van Wezel

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.

Promotie

Protein–protein complexes are formed via transient states called encounter complexes that greatly influence the formation of the stereospecific complex.

My work focuses on a class of astronomical objects called protoplanetary disks.

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

Promotor: Prof.dr. H.V.J. Linnartz

'Wat als we één avond alle lichten uitdoen. Dat idee dook af en toe in mijn hoofd op. En op een dag vertelde ik het aan een taxichauffeur, en hij zei:

In this thesis chemical and physical processes in the ice mantles on interstellar dust grains are studied.

Stellar feedback is a crucial ingredient in the evolution of galaxies.

To study how planetary systems come into existence we study much younger systems still in formation.