Promotor: W. Jaffe, Co-promotor: K. Meisenheimer

This thesis presents the anharmonic infrared spectra of a series of polycyclic aromatic hydrocarbons. Comparisons and characterizations are made based on high-resolution low-temperature gas-phase experimental spectra.

This thesis is about the study of hydrocarbons via infrared spectroscopy.

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

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.

Understanding how chemical complexity emerges during star formation requires connecting molecular material preserved in interstellar ices with that observed in the gas phase after protostellar heating begins.

Promotor: H.J.A. Rottgering, Co-Promotor: R.J. van Weeren

Bernhard Brandl benoemd tot hoogleraar Infrared Astronomy

The goal of the research presented in this thesis was to explore the chemical space of ruthenium(II) photocages, investigate their ability to host potent chemotherapy drugs, and to red shift the activation wavelength of the most promising PACT candidates to conduct biological studies.

A dense region of a gaseous and dusty cloud collapses to form a protostar surrounded by a disk and an envelope. This thesis uses both observations and models to study physical and chemical conditions of these protostellar systems which are likely where planets start to form.

Promotor: I. A. G. Snellen, Co-promotor: M. A. Kenworthy

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

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

On the largest scale, the Universe resembles a cosmic spiderweb. Most galaxies coexist in small groups within the threads of this web. At the nodes of the threads are enormous groups of galaxies forming the largest structures in the universe still held together by gravity: clusters of galaxies.

An Active Galactic Nucleus (AGN) is a highly luminous region at the center of a galaxy, powered by the accretion into a supermassive black hole and emitting energy from radio waves to gamma rays, often outshining the host galaxy.

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

Following the Big Bang, structure in the Universe started collapsing under the force of gravity. This resulted in the formation of the first stars, galaxies and clusters of galaxies.

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

This thesis is largely an experimental study on the formation of solid-state simple and complex organic molecules in the H2O-rich and CO-rich ice phases of dense interstellar clouds and dark cores.

The radio sky harbours both galactic and extragalactic sources of arcminute- to degree-scale emission of various physical origins. To discover extragalactic diffuse emission in the Cosmic Web beyond galaxy clusters, one must image low–surface brightness structures amidst a sea of brighter compact fore-…

Complex Organic Molecules (COMs) have been detected in objects across different stages of stellar evolution.

Promotor: J.G.E.M. Fraaije, Co-Promotor: A. Kros

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.

Barrier function is the natural role of the skin. The lipid matrix present in the outermost layer of the skin, the stratum corneum is important for this function.

Metal-based prodrugs based on ruthenium(II) polypyridyl complexes have proven to be very suitable for application in both photodynamic therapy (PDT) and photo-activated chemotherapy (PACT).

Het DESHIMA-instrument van Nederlands-Japanse makelij heeft de eerste praktijktests doorstaan bij het meten van de afstanden en leeftijden van verre sterrenstelsels. De kern van het instrument is een chip ter grootte van twee euromunten die 49 tinten ver-infraroodlicht meet. De ontwikkelaars van de…

Een internationaal team van astronomen heeft tien keer zoveel super heldere sterrenstelsels waargenomen als volgens theoretische modellen mogelijk zou moeten zijn. Mede-auteur en directeur van de Sterrewacht Huub Röttgering vertelt in Wetenschap Vandaag over het onderzoek.

The lipids in the uppermost layer of the skin, the stratum corneum (SC), play an important role in the skin barrier function. The three main SC lipid classes are ceramides (CER), cholesterol and free fatty acids.

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

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

In this thesis, we use low-frequency and high-frequency radio observations to address the following questions regarding quasars: is the radio loud/quiet quasar dichotomy real?

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

Promotor: Prof.dr. C.U. Keller

Promotor: M.A.G.J. Orrit

A large diversity of exoplanetary systems has been found, but it is still unclear what drives this diversity.

The aromatic infrared bands (AIBs) seen throughout the interstellar medium (ISM) are generally thought to be carried by polycyclic aromatic hydrocarbons (PAHs) and their nitrogen analogues (PANHs).

Stars and planets form within cold, dense clouds of gas and dust drifting through interstellar space. Although dust makes up only a small fraction of this material, it plays a key role in shaping the chemical evolution of these environments.

Astronomical observations of cold regions in the universe show a rich inventory of ices. Part of these ices may end up on planets like our own, but in that journey they will be exposed to considerable amounts of radiation.

A century ago, it was unclear whether the stars in the sky were clustered in groups, or widely spread in the universe.

Promotor: J. A. Bouwstra

Over the last three decades, the discovery of exoplanets has revealed the boundless variety of worlds beyond our own Solar System⁠. Majority of planetary systems contain short-period planets that are larger than Earth but smaller than Neptune⁠.

Ze vond alle studies interessant, maar koos voor Sterrenkunde. En nu ontrafelt hoogleraar Mariska Kriek de onstaansgeschiedenis van sterrenstelsels met de James Webb telescoop. KIJK-redacteur Laurien Onderwater praat met haar over haar over haar carrièrepad.

This thesis aims to demonstrate how the achromatic nature and design flexibility of liquid-crystal optics can be used to improve high-contrast imaging instruments to facilitate detailed exoplanet characterization.

Promotor: E. Bouwman, Co-promotor: S. Bonnet

Microbial rhodopsins are photosensitive pigments implemented in the growth and adaptation of a large population of microorganisms.

This thesis takes steps toward understanding the interaction between gas-phase and solid-state molecules in star- and planet-forming regions.

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

Na 25 jaar is het deze december eindelijk zo ver: de lancering van de lang verwachte James Webb ruimtetelescoop. Leidse astronomen kijken vol spanning mee: niet alleen waren zij betrokken bij de bouw van belangrijke instrumenten aan boord, de telescoop zal ook vele nieuwe geheimen van het heelal onthullen,…

Promotie

Bernhard Brandl, de nieuwe Leidse hoogleraar Infraroodastronomie, bouwt mee aan instrumenten waarmee de grootste telescopen ter wereld worden uitgerust. Met die telescopen kan de mens in het heelal objecten observeren die soms meer dan dertien miljard jaar oud zijn. Op 26 september houdt Brandl zijn…