Promotor: Prof.dr. M. de Jong, Co-Promotor: Dr. A.J. Heijboer

This thesis revolves around the electronic spectroscopy of molecules in the laboratory and the search for the carriers of the diffuse interstellar bands (DIBs).

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

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

The focus of the dissertation

Promotor: M. de Jong, Co-Promotor: Samtleben

The theoretical explanation of cosmic acceleration is nowadays one of the biggest puzzles in cosmology.

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: A. Achúcarro Co-promotor: A. Boyarsky

In this work the reconstruction of a tau neutrino signal in the KM3NeT detector is discussed.

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

Hot astrophysical plasma is ubiquitous in the Universe, from comets in our Solar system to the largest scale structures -- the cosmic web filaments. These hot plasmas, with the temperature of a few millions of degrees, are often observed in the X-ray wavelength range.

For the first time, scientists have traced back a high-energy neutrino to its source in space. It was produced by a so-called blazar—a supermassive black hole. Researchers from neutrino detector IceCube report this in Science. ‘This is a milestone for neutrino science,’ says physicist Dorothea Samtleben…

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I have studied the hot, diffuse gas around and between galaxies. Specifically, I have used the EAGLE numerical simulations of galaxy formation to predict the properties of this gas, and I have used those properties to predict specific observables: soft X-ray absorption and emission lines.

Promotor: J.S. Kaastra Co-promotor: E. Constantini

In this thesis, we present new laboratory data of interstellar dust analogues.

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

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

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

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

An international team of astronomers from Leiden Observatory and others, has for the first time mapped a piece of the dark, cosmic web. The research strengthens the hypothesis that the young universe consisted of huge numbers of small groups of newly formed stars. The astronomers publish their findings…

This dissertation provides a comprehensive overview of the grammar of Bantawa, a Kiranti (Rai) language spoken in Eastern Nepal.

Dishoeck

This thesis examines silicon pore optics (SPO), a technology that exploits silicon wafers from the semiconductor industry to create extremely high quality X-ray optics, by studying its manufacturing process, applications, and prospects.

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

The largest galaxies in the Universe feed off cosmic oceans, which helps them grow. This is the presumption of an international team of scientist with two Leiden astronomers, based on observations of the ‘Spiderweb’ galaxy. The researchers published their evidence in Science on 2 December 2016.

My work is motivated by the necessity to extend Standard Model of Particle Physics in order to explain three observed phenomena that this great theory fails to accommodate

A team of laboratory astrophysicists from Leiden University managed to make glycerol under conditions comparable to those in dark interstellar clouds. They allowed carbon monoxide ice to react with hydrogen atoms at minus 250 degrees Celsius. The researchers publish their findings in the Astrophysical…

Galaxies are often found in clusters, which contain many “red and dead” members that stopped forming stars in the distant past. Now, an international team of astronomers, led by Andra Stroe of Leiden Observatory and David Sobral of Leiden and the University of Lisbon, has discovered that these comatose…

In this thesis we study the landscape of gravitational models which modify GR by introducing an additional scalar degree of freedom (d.o.f.) to source Cosmic Acceleration.

The Netherlands Organisation for Scientific Research NWO allocates nearly € 19.5 million to a Dutch cluster that contributes to the development of an X-ray camera and spectrograph for the new European space telescope Athena. Leiden Observatory is one of the members of the cluster.

Scientists from Leiden and Delft recently discovered old texts using X-ray radiation. The subject was reported in the English newspaper The Guardian.

Het project heeft plaats gevonden in de KM3NeT Nikhef Amsterdam groep onder begeleiding van Dr. D.F.E. Samtleben en Prof.dr.ir. T.H. Oosterkamp. De titel van de presentatie is:

Physicists, including Dorothea Samtleben from Leiden University, are building a giant underwater telescope to unravel the origin of neutrinos and to solve the mystery surrounding dark matter. The first detector has now been installed. Once it is finished, the telescope will be three cubic kilometres…

This thesis is dedicated to the exploration of the primordial dark ages: unknown physics during the earliest stages of the Universe’s expansion that have not yet been directly probed by observations. Cosmic inflation is a burst of exponential expansion of space after the “Big Bang”.

A special type of mirror to reflect X-rays has more possible applications than space research. Targeted radiation therapy for cancer, for example. Next to his full-time job, physicist David Girou mapped out the possibilities. He will receive his PhD on 14 June.

'Don’t Let the sunny weather fool you' a film made by Visual Ethnography alumna Guusje Meeuwissen has been selected for the RAI film festival in London this year. It's a short film about the everyday lives of a farmer and a fisherman in the Philippines, and their capacity to adapt to a changing natural…

Pulsars were first discovered in 1967 and since then the population has grown and expanded over several wavelengths.

Promotor: J.W.M. Frenken, Co-Promotor: R. Felici

This project embarks on empirical analysis of popular psycho-physical practices in contemporary Korea.

Promotor: Prof.dr. M. Ubbink

PhD Defence

Building the neutrino detector KM3NeT on the Mediterranean Sea floor has picked up pace. Five detection lines, each carrying eighteen detectors, have been sunk and installed, and the first measurement data are coming in, says neutrino physicist Dorothea Samtleben.

Promotor: K. Kuijken, Co-Promotor: H. Hoekstra