Titan, the largest moon of Saturn, is a place like nowhere else in the Solar System. A dense, nitrogen-rich atmosphere, very similar to the one on Earth, is the place where very interesting photochemistry, started by solar photons, forms organic (made of C, H, N and sometimes O), molecules that are the precursors of the haze present in the atmosphere. The haze particles than "rain" on the surface where they are moved by wind to form dunes, lakes, and seas of hydrocarbons. Understanding the inventory of molecules present on the atmosphere and how this evolves responding to the physical and chemical conditions it is of great importance because Titan is one of the best places in the Solar System to look for life.

OBJECTIVE: The project's goal is to quantify the presence and population of a specific class of organic molecules, Polycyclic Aromatic Hydrocarbons, in the upper atmosphere of Titan. To achieve this goal, the student will analysed spectra of Titan's atmosphere recorded by the Cassini mission using available spectroscopic databases. The student will make use of available scripts and adjust them to the scientific problem at hand. This project will give experience in working with molecular spectroscopic data for application to astronomical problems and in advancing programming skills.

PREREQUISITES: Rudimentary knowledge of python and atomic spectroscopy is beneficial.

RESOURCES: Access to a normal laptop/workstation with linux/unix would be useful.

Fast radio bursts (FRBs) last for much less than the blink of eye and originate in distant galaxies, billions of lightyears away. We are still trying to understand what produces the FRBs. The hyper-magnetic neutron stars known as magnetars are a leading contender, but can they explain the variety of different FRBs we have observed? Some FRBs repeat, whereas others apparently do not. Some FRBs are found near star-forming regions in their host galaxies, whereas others live where only old stars are expected. This is confusing, and suggests that there may be multiple types of FRB progenitors.

OBJECTIVE: The project aims to better understand the diverse FRBs we observe and to make connections to other types of extreme astrophysical phenomena like magnetars, interacting binaries and accreting black holes. To do this, we will use data from the Nançay radio telescope, which is monitoring many of the known repeating FRB sources. The student will analyse these data to detect FRBs and will then analyse the properties of these bursts, including their time-variable dispersion measure, Faraday rotation measure and burst rate. These diagnostics teach us about the nature of the source and its local environment.

PREREQUISITES: No prior knowledge of the field is required but experience with programming in Python and working in a Linux environment is preferred.

RESOURCES: The computationally intensive aspects of the FRB search will be performed on our DRAGNET computing cluster. We will lend a laptop computer if need be.

White dwarf stars are the most common type of stellar remnant. In rare cases, binary star evolution can form very close white dwarf binary systems where one star (donor) slowly transfers mass to the white dwarf star: Cataclysmic Variable stars (CV). Because of conservation of angular momentum, the mass does not directly flow onto the white dwarf, instead it spirals in and forms a so-called accretion disk. These disk periodically become unstable and ‘explode’, causing the binary system to become 10-100 times brighter than usual. We call these ‘explosions’ dwarf novae. 

While most accreting white dwarf have a regular red dwarf as a donor, a small fraction have another white dwarf as a donor star and consist entirely of Helium; and are called Helium Cataclysmic Variables (or ‘AM CVn’-type stars). Because the donor star is a very compact white dwarf, the binary orbital period is very short, less than 1hr! Because of this, they are also strong sources of gravitational waves. About 80 of these Helium-CV systems have been found in the last 40 years, but we still do not know how exactly they are created and what their properties are, how many there are in our Galaxy, and how strong their gravitational wave emissions are.

OBJECTIVE: The main objective is to find new Helium-Cataclysmic variables. To do this, you will systematically inspect all dwarf novae explosions detected by robotic telescopes, mainly the Zwicky Transient Facility. You will get familiar with ZTF data and the different kinds of outbursting stars ZTF is finding. To identify Helium CVs, you will search for periodic eclipses that can be used to measure the CV orbital period, and/or measure the strength and duration of the outbursts (Helium CVs typically have shorter and weaker outbursts). If you want to get some background information: in this youtube video I talk a bit about ZTF and CV stars.

PREREQUISITES: Knowledge in coding with Python is preferred but not mandatory. Some basic experience with linux is also helpful, but not required.

RESOURCES: A normal computer/laptop should suffice, with a working Python installation.

Radio transient astronomy has taken off during the past decade, thanks to excellent new radio telescopes coming online and increases in computational power. Exciting detections of strange sources that still need identifying have been made including the Galactic Burster, a LOFAR transient, dispersed transients by AARTFAAC and recently an MWA discovery of a possible unusually slow magnetar. Each detection leads to the chance of discovering a whole new population of transient sources. In this project you will take data obtained by survey experiments from a world class radio telescope, either LOFAR or MeerKAT, and search for new transient sources on timescales ranging from seconds to months. You will process these data using our successful transient detection pipeline and help develop new techniques with our team.

OBJECTIVE: The key goal of this project is to search for and identify transient and variable sources in a radio image dataset by applying existing techniques developed for other datasets. The second objective is to develop and trial new techniques to filter transient candidates. The student will learn to process radio images and how to handle systematic effects in these data.

PREREQUISITES: Some knowledge of Python is preferred.

RESOURCES: The student will be connecting to computer resources in Amsterdam, so a standard computer or laptop is sufficient. Linux or OS operating system is ideal; however, there will be alternative options for Windows users.

Gamma-ray bursts and their afterglows are among the brightest objects in the Universe. Other than trying to understand how they work, they offer us an opportunity to detect objects from soon after the first stars formed, perhaps only 500 Myr after the Big Bang. How likely this is to be of practical importance depends on how bright we expect them to be and how many of them occur at high redshift. Even if they are rare and difficult to detect, they offer such a unique opportunity to learn about the early Universe that they may be well worth looking for.

OBJECTIVE:  In this project we will explore how bright high might actually be, and what it would take to use them to probe the early history of our Universe. The student will learn about the radiation processes in gamma-ray bursts and about how the observed quantities change with redshift, and calculate how many GRBs one might see from redshift 6 and beyond. 

PREREQUISITES: No prior knowledge of GRBs is needed, but the student should be familiar with python programming and have a laptop own which python scripts can run. (The project does not require large computing resources.)

RESOURCES: A normal computer/laptop should suffice, with a working Python installation.