"PhD Position: Gravitational-Wave Astronomy and Massive Stellar Binary Evolution"

Job Description

Join a pioneering PhD project exploring how massive stars evolve into gravitational-wave sources. Combine stellar physics, simulations and cutting-edge data to uncover the origins of black holes and neutron stars, linking theory with the latest discoveries in this rapidly growing field.

It has been just over a decade since the first detection of gravitational waves, marking the birth of a new field in astronomy. Since then, the number of detections has grown rapidly: from one, to a few, to hundreds, revealing entire populations of gravitational-wave sources. These signals are produced by black holes and neutron stars, the compact remnants of massive stars.

Many questions on how these populations form remain. To solve this puzzle, we must understand how massive stars are born, interact in binary systems, and how they end their lives as black holes or neutron stars. This will be the topic of this PhD thesis.

As a PhD candidate, you will conduct fundamental research on the evolution of massive binary stars, with a special focus on the systems that give rise to gravitational-wave sources.

This theoretical project will be at the intersection of stellar physics, computational astronomy and an unprecedented amount of data driven by observation. You will learn to run simulations on high-performance computing clusters, ranging from broad parameter studies with rapid binary-population synthesis codes to detailed stellar evolution calculations with 1D stellar evolution codes. The models you develop will be directly linked to new and upcoming observations, including the just-released 4th gravitational-wave observations (O4, released in August 2025) and the Gaia DR4 dataset (expected mid-2026).

Your duties as a teaching assistant cover about 10 percent of your work time, spread over the course of the appointment.

Requirements

You hold a Master's degree in astronomy/physics or a related field, or you expect to obtain your Master’s degree around the starting date of the appointment.

You bring curiosity and enthusiasm, enjoy thinking critically, communicate openly, and take initiative.

You are able to work in a team as well as independently.

You have excellent writing and verbal communication skills in English.

Conditions of Employment

We will give you a temporary employment contract (1.0 FTE) of 1.5 years, after which your performance will be evaluated. If the evaluation is positive, your contract will be extended by 2.5 years (4-year contract).

You will receive a starting salary of €3,059 gross per month based on a 38-hour working week, which will increase to €3,881 in the fourth year (salary scale P).

You will receive an 8% holiday allowance and an 8.3% end-of-year bonus.

We offer Dual Career Coaching. The Dual Career Coaching assists your partner via support, tools, and resources to improve their chances of independently finding employment in the Netherlands.

You will receive extra days off. With full-time employment, you can choose between 30 or 41 days of annual leave instead of the statutory 20.

Additional Employment Conditions

Work and science require good employment practices. This is reflected in Radboud University's primary and secondary employment conditions. You can make arrangements for the best possible work-life balance with flexible working hours, various leave arrangements and working from home. You are also able to compose part of your employment conditions yourself, for example, exchange income for extra leave days and receive a reimbursement for your sports subscription. And of course, we offer a good pension plan. You are given plenty of room and responsibility to develop your talents and realise your ambitions. Therefore, we provide various training and development schemes.

Employer

Radboud Universiteit Faculty of Science The Faculty of Science (FNWI), part of Radboud University, engages in groundbreaking research and excellent education. In doing so, we push the boundaries of scientific knowledge and pass that knowledge on to the next generation.

We seek solutions to major societal challenges, such as cybercrime and climate change and work on major scientific challenges, such as those in the quantum world. At the same time, we prepare our students for careers both within and outside the scientific field.

Currently, more than 1,300 colleagues contribute to research and education, some as researchers and lecturers, others as technical and administrative support officers. The faculty has a strong international character with staff from more than 70 countries. Together, we work in an informal, accessible and welcoming environment, with attention and space for personal and professional development for all.

Radboud University At Radboud University, we aim to make an impact through our work. We achieve this by conducting groundbreaking research, providing high-quality education, offering excellent support, and fostering collaborations within and outside the university. In doing so, we contribute indispensably to a healthy, free world with equal opportunities for all. To accomplish this, we need even more colleagues who, based on their expertise, are willing to search for answers. We advocate for an inclusive community and welcome employees with diverse backgrounds, cultures, and perspectives. Will you also contribute to making the world a little better? You have a part to play.

Department

Your PhD project will be supervised by Dr. Lieke van Son (Radboud University) and will be carried out in a highly international setting. Collaboration with international research groups across the globe is expected.

This PhD position is embedded in the Astrophysics Department at the Institute for Mathematics, Astrophysics and Particle Physics (IMAPP) at Radboud University (Nijmegen, Netherlands). We are a very tight-knit and socially active department, currently home to 18 faculty members (junior and senior) and about 65 postdoctoral researchers and PhD candidates. Research at the department covers a broad range of topics, including stellar physics, black hole and accretion physics, gravitational waves, cosmic rays, and instrumentation.

Additional Information

You can apply only via the button below. Address your letter of application to Dr. Lieke van Son. Please include your CV, a motivation letter explaining your interest and fit for this research, a transcript of grades from your MSc program and the names and email addresses of at least two referees who will provide letters of recommendation. We look forward to receiving your application.

The first interviews will take place in the first week of December. You will preferably start your employment on January 2026 (open to discussion).