What is so fascinating about your research area?
Sebastian Kamann: In my research, I try to understand the evolution of massive star clusters, densely packed ensembles of sometimes millions of stars that are held together by their mutual gravity. What makes this research exciting is that we can use basic physical principles, like Kepler’s laws, to make new discoveries. For example, a widely debated question is whether star clusters can nurture black holes. To answer this question, we monitor the velocities of stars and look for periodical variations that suggest they orbit a massive companion – just like our Earth orbits the Sun. Only that in our case, the companions we are looking for, the black holes, are invisible. So, their gravity is our only chance of detecting them.
Which central message should your students remember?
Sebastian Kamann: The value that comes from collaborating with others. These days, important discoveries are not made by individuals, but by teams combining different skills. Modern astrophysical data are complex, and no single researcher masters every aspect of their analysis. Therefore, I think that asking for help is a key to success in research. Furthermore, working together with your fellow scientists is a rewarding experience. Not only because you learn from them, but also because you realize how your skills enable others to do groundbreaking research.
Why did you decide to do research and teach at our Faculty?
Sebastian Kamann: I have been collaborating with the group of Glenn van de Ven for a long time and we have several projects ongoing. Above, I mentioned our efforts to find black holes in star clusters. Unfortunately, the fraction of black holes that have a visible companion is small and most black holes will remain hidden. But through dynamical modelling, a method in which the Vienna group has world-leading expertise, we can still infer the total number of black holes in a cluster.
I got excited about the idea of teaching a block course on star cluster dynamics at the Faculty because it gives the students an opportunity to work with state-of-the-art astronomical data and address a genuine research problem. Thanks to the participation of Francisco Aros from Glenn’s group, we can also introduce the students to different dynamical modelling techniques.
Which three publications characterise your work?
- Kamann, S., Wisotzki, L., Roth, M. M. (2013): "Resolving stellar populations with crowded field 3D spectroscopy", Astronomy and Astrophysics, 549, A71. – This was my first ever publications, on a new data analysis technique that opened many doors for me throughout my career.
- Kamann, S., et al. (2018): "A stellar census in globular clusters with MUSE: The contribution of rotation to cluster dynamics studied with 200 000 stars", Monthly Notices of the Royal Astronomical Society, 473, 5591. – The paper presents the results from a large start cluster survey I led and that defined the first decade of my scientific career.
- Giesers, B., et al. (2018): "A detached stellar-mass black hole candidate in the globular cluster NGC 3201", Monthly Notices of the Royal Astronomical Society, 475, L15. – This work was led by a PhD student I co-supervised, who made the first detection of a dormant black hole using the star cluster survey data presented in the previous publication.
Thank you for visiting our Faculty!
About the Person
- Sebastian Kamann is a UKRI Future Leaders fellow and Reader in Astrophysics at the Astrophysics Research Institute of Liverpool John Moores University in the UK. After finishing his PhD at the Leibniz-Institute for Astrophysics Potsdam (Germany) in 2013, Dr. Kamann moved to the University of Göttingen as a postdoctoral researcher. In 2017, he moved to Liverpool, where he worked as postdoctoral researcher until being awarded a seven-year Future Leaders fellowship and becoming a member of the academic staff in 2020.
In research, Dr. Kamann tries to understand the evolution of star clusters using integral-field spectroscopy. He is a member of the consortium that built the MUSE integral field spectrograph for the Very Large Telescope. Using MUSE, Dr. Kamann can study the motions of 1,000s of cluster stars simultaneously and explore questions such as the properties of binary stars, the retention of stellar-mass black holes in the clusters, and the existence of the enigmatic intermediate-mass black holes.
