The Faculty of Science and Leiden Observatory are seeking a:

PhD Candidate in Radio Studies of Galaxy Clusters

We offer a four-year PhD position within the LOFAR group at Leiden Observatory, supervised by Dr. Reinout van Weeren. The project aims to advance our understanding of the formation of galaxy clusters, including their galaxy populations and non-thermal components such as magnetic fields and cosmic rays. This position is suited for candidates with a strong interest and background in extragalactic astrophysics, observational astronomy, and/or computational methods. Depending on the candidate’s expertise and interests, the project may involve large-scale data analysis using high-performance computing (HPC) infrastructure, observations with additional radio facilities, and multi-wavelength studies. The project will benefit from Leiden Observatory’s close involvement in the LOFAR2.0 upgrade and is embedded within the group working on extragalactic LOFAR surveys. The position is funded through an NWO Vici grant awarded to Dr. van Weeren.

The candidate is expected to participate in the Leiden PhD program, including participation to the NOVA fall school, workshops and duties as teaching assistant at Leiden Observatory. The student will be a member of the LOFAR research group and a member of the Leiden Graduate School of Science.

Selection Criteria:
We are seeking an enthusiastic and motivated candidate. The ideal applicant has recently completed, or is about to complete, a Master’s degree in a relevant field (astronomy, physics, computer science, or other). Strong communication skills in English—both written and spoken—are essential. Experience with handling radio interferometric observations, and/or extragalactic research is particularly advantageous.

Research at our faculty:
Leiden University’s Faculty of Science is a vibrant and internationally oriented environment where researchers and students collaborate across disciplines to expand the frontiers of knowledge. Research at the faculty spans a broad spectrum: mathematics, artificial intelligence, computer science, astronomy, physics, chemistry, bio-pharmaceutical sciences, biology, and environmental sciences. With over 1,300 staff members and nearly 4,000 students, the faculty has experienced significant growth and is situated in the heart of the Leiden Bio Science Park—one of Europe’s largest science hubs, fostering close interaction between academia and industry. For more information, please visit the faculty page.

Leiden Observatory is the astronomical institute of the Faculty of Science at Leiden University. With a rich history and a leading role in international astronomy, we offer a dynamic work environment where cutting-edge research and top-level education come together. Our academic programs include a Bachelor and Master degree, complemented by a renowned PhD program. Together with over 180 dedicated staff members we are committed to academic innovation and fostering a close-knit, inclusive community where everyone feels welcome and valued. For more information about Leiden Observatory, see here.

Terms and conditions
- We offer a full-time appointment of initially one year. After a positive evaluation of the progress of the research, teaching evaluations, personal capabilities and compatibility, the appointment will be extended for another three years.
- The gross salary ranges from € 2.901 per month in the first year to € 3.707 gross per month in the fourth year based on a full-time position (pay scale P).
- Leiden University offers an attractive benefits package including pension build-up, paid parental leave and additional holiday (8%) and end-of-year bonuses (8.3%). Our individual choices model gives you some freedom to assemble your own set of terms and conditions. Candidates from outside the Netherlands may be eligible for a substantial tax break. For more information, see our website.
- All our PhD candidates are embedded in the Leiden University Graduate School of Science.
Leiden University is strongly committed to diversity within its community and especially welcomes applications from members of underrepresented groups.

Application details:
- Deadline: May 11th 2026
- Starting date: between September and December 2026
- Requirements: MSc degree in relevant field (astronomy, physics, computer science, or other) by starting date

Application documents:
- Cover letter, including name and e-mail of recommendation letter writers (1 page)
- Research statement discussing research background and interest (1 page)
- CV
- a list of all university courses taken and transcripts of grades obtained
- 2 (or 3) recommendation letters

Instructions: Upload the application documents by May 8th through the system below and fill out the information for your letter writers. Remind your letter writers to upload their recommendation letters by this deadline as well. Incomplete applications will not be considered.

For further inquiries, send an e-mail to Reinout van Weeren (rvweeren@strw.leidenuniv.nl).