1. Reverberation Mapping Simulations of Active Galactic Nuclei

ESA supervisor: Bert Vander Meulen
Collaborator(s): Matteo Guainazzi

Site: ESTEC

Active galactic nuclei (AGNs) are the luminous central regions of massive galaxies, powered by accretion onto a supermassive black hole. Currently, it is not possible to spatially resolve AGNs in observations, due to their compact sizes at large distances. The most effective way to map out the circumnuclear environment, is to use light echoes (or reverberations), produced when the AGN emission is reflected off the surrounding material. When the brightness of the central AGN varies, the reflected emission will vary in response. However, this response will be delayed with the light travel time towards the surrounding material, which can be used to map out the geometry of the unresolved environment. However, current state-of-the-art radiative transfer codes do not track light travel times, and therefore they cannot study or exploit this reverberation phenomenon.

The goal of this student internship is to study the reverberation mapping technique by performing radiative transfer simulations in 3D circumnuclear media and analysing the resulting delay curves to infer geometrical information on the AGN environment. This is a computational project, focussed on running Monte Carlo radiative transfer simulations and interpreting large amounts of simulated time series in Python. This project includes extending the Monte Carlo radiative transfer code SKIRT (written in C++) to record photon travel times (as needed to produce delay time series). However, no prior experience with C++ will be required.

Project duration: 6 months.

Desirable expertise or programming language:

  • Experience with Python programming/scripting is essential.
  • Some experience with command line computing (e.g. terminal, Unix) is desired.
  • Basic knowledge of C++ programming is beneficial, but not essential.
  • Knowledge of extragalactic astronomy is desired, but not essential.
  • Enthusiasm and curiosity for exploring large astronomical datasets.

To apply for this project please fill in an online application form through the following link.

To see the full list of Internships available at ESA please go to our website for ESA Career Opportunities.