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

Visualizing the internal structure is a crucial step in acquiring knowledge about the origin, state, and composition of cultural heritage artifacts. Among the most powerful techniques for exposing the interior of cultural heritage objects is computed tomography (CT), a technique that computationally…

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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.

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.

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.

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.

Professor of Computer Science Joost Batenburg has received half a million euros from the Dutch Research Council (NWO) to improve the conservation of historical paintings with 3D X-ray imaging.

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

X-ray and CT scanners are widely used devices in research, diagnostics and the industrial sector. And yet they are not nearly as fast and accurate as we would like. Mathé Zeegers is researching the newest technique in the field at the Centre for Mathematics and Computer Science: spectral X-ray imaging.…

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.

Through the clever use of two types of telescopes, a team of researchers has produced stunning images of clusters of galaxies. This not only produces beautiful images, but also provides more information about the enormous amounts of energy released around supermassive black holes in clusters. The astronomers,…

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

Promotor: Prof.dr. M. Ubbink

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

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

Promotor: Prof.dr. J.W.M. Frenken

Radiography is an important technique to inspect objects, with applications in airports and hospitals. X-ray imaging is also essential in industry, for instance in food safety checks for the presence of foreign objects.

Assistant Professor Karlsson Linnér, who works at the Department of Economics, is one of the recipients of a Veni grant. His research on the accuracy of preventive genetic testing is a fine example of the intersection of economic science and law.

To construct catalysts that can produce fuels from CO2 innumerable times, we need to learn much more about how catalysis works. Irene Groot is conducting groundbreaking research into catalysis at the atomic level.

An X-ray scanner, some small metal balls, and a newly developed algorithm. That is all you need to make a 3D model that enables you to look inside art objects without dismantling them. Thanks to the research of Francien Bossema (Centrum Wiskunde & Informatica and Leiden Institute of Advanced Computer…

The central theme of Rik Mom’s research group is to identify what the electrode-electrolyte interface looks like when electrocatalysis is taking place. Using specialized forms of Raman and X-ray spectroscopy, we study the chemical state and bonding environment of the electrode surface and near-surface…

Archaeometric analysis of glazed pottery assemblages from the Early Byzantine to the Early Modern periods in the Aegean.

Promotor: J. A. Bouwstra

Tomography is a powerful technique to non-destructively determine the interior structure of an object.Usually, a series of projection images (e.g.\ X-ray images) is acquired from a range of different positions.

Promotor: K.J. Batenburg

The Department of Biophysical Structural Chemistry studies how biological systems work at the molecular level through high-resolution structural analysis. Using state-of-the-art techniques in structural biology such as cryo-electron microscopy and X-ray crystallography we gain crucial insights into…

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.

The research aims to explore the evolutionary adaptability of enzymes and the impact of temperature on protein evolution pathways, using M. tuberculosis β-lactamase BlaC as the object of study. Enzymes inherently embody a delicate balance between activity and stability, and the acquisition of new enzymatic…

PhD defence

A technique originally developed for satellite imaging can now be used to recover pictographic texts from underneath the surface of a five hundred year old Mexican manuscript.

From nanoparticles to colliding ice planets and from biological origami to new x-ray scanner techniques: this year again, our scientists have made wonderful discoveries. From the largest numbers to the smallest molecules and from the oldest galaxies up to the latest algorithms, take a look at each institute's…

Agricultural foods naturally vary in their detailed internal structure. To facilitate early detection of health hazards due to contamination or disease, predict maturity and minimize wastage, it is critical to take into account the internal characteristics of each individual product, as these enable…

What is neutron star matter?

It has now been well established that shocks and turbulent motions in the intra-cluster medium (ICM) generated through cluster mergers can produce large-scale synchrotron emission.

The skin barrier function is provided by the stratum corneum (SC). The lipids in the SC are composed of three lipid classes: ceramides (CERs), cholesterol (CHOL) and free fatty acids (FFAs) which form two crystalline lamellar structures. In the present study, we investigate the effect of CER chain length…

X-Ray Diffraction (XRD), Nuclear Magnetic Resonance (NMR) and Cryo-electron microscopy (Cryo-EM) are the three main methods for solving structures of macromolecules.

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.

Exploring the largest structures in the universe by looking at the tiniest particles? Lydia Stofanova, PhD candidate at Leiden Observatory and SRON Netherlands Institute for Space Research, dives into this intricate connection. In her PhD research, she explored how elements like oxygen influence the…

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

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