I have a background in astronomy. I did my bachelor and master in Astronomy at Leiden University. My main research interests are in gravitational lensing, supernova-cosmology, galaxy formation and evolution of galaxies. I focus on the (development) of methods/algorithms for modelling and statistics applied in these fields.
During my studies in Leiden I worked on several research projects:
1. The influence of systematic error on the constraint of cosmological parameters. This was my bachelor project, supervised by Prof. Konrad Kuijken, I investigated the possibility that a systematic error in the luminosity of Type Ia supernovae, which are used to determine cosmological parameters, could lead to a cosmological model without dark energy. A large data set of Type Ia supernovae was used to determine the influence of three systematic errors: square root, linear and quadratic. We used chi-square minimization to find the best fitting values of the cosmological parameters for the distance modulus in a general model with a flat Λ Universe, and another model of a Λ Universe with ω as a parameter. As a result, only in the Λ -Universe with a density parameter ω =-1 and a positive square root error was it possible to show a trend towards a universe without vacuum-energy.
2. Computer simulations of galactic magnetic fields. This was my minor research project, supervised by Dr. Anders Johansen and Dr. Peter Katgert, I worked with the Pencil code, which is a numerical high-order finite-difference code for compressible hydrodynamic flows with magnetic fields. We performed 3D computer simulations of turbulent magnetic fields in a galactic disc in order to compare the magnitude of the small- and large-scale magnetic fields to observations.
3 Solar modulation of cosmic rays. This was my major research project supervised by Dr. Jörg Hörandel from Radboud University Nijmegen on the solar modulation of cosmic ray fluxes using data from the Pierre Auger Observatory and several neutron monitors. Since low energy cosmic rays are charged particles, they are easily deflected by magnetic fields and are influenced by the solar magnetic and geomagnetic fields. A strong correlation was found between the Pierre Auger data and the neutron monitors for the four transient Forbush-decrease events.
Besides these research projects, for some of my courses I also had to work on some interesting problems like mesh-grid-refinement, numerical integrals, computational analysis of the geometry of spiral arms in galaxies and simulation of stellar evolution and galaxy-evolution.
Research | Current
Searching for the missing dark satellite galaxies
Areas of expertise
Gravitational Lensing, MCMC-methods, Bayesian Statistics, Cosmology