Projevy přítomnosti cirkumbinárních disků při splynutí hvězd
| Thesis title in Czech: | Projevy přítomnosti cirkumbinárních disků při splynutí hvězd |
|---|---|
| Thesis title in English: | Circumbinary disks around stellar mergers |
| Academic year of topic announcement: | 2024/2025 |
| Thesis type: | diploma thesis |
| Thesis language: | |
| Department: | Institute of Theoretical Physics (32-UTF) |
| Supervisor: | doc. Mgr. Ondřej Pejcha, Ph.D. |
| Author: | |
| Advisors: | Damien Lucien Michael Gagnier, Ph.D. |
| Guidelines |
| One of the exciting revelations in astrophysics of the past 10 years has been the realization that we can directly observe mergers of stars. Although the number of observed events grows only slowly, we have already witnessed several surprising features that defy previous theoretical expectations. One of these surprises is that the observed events show relatively slow brightening, which has been interpreted as a gradual mass loss in the orbital plane of the binary. Some of the observed events even show quasiperiodic oscillations that accompany the gradual rise of brightness.
One way to think the situation is that the binary surrounds itself with a circumbinary disk, which allows us to translate the theoretical developments from circumbinary disks to stellar mergers. Specifically, circumbinary disks often exhibit an overdensity called "lump", which orbits the barycenter with frequencies several times smaller than the central binary. The main goal of this thesis is to investigate the dependence of the lump orbital frequency on properties of the central binary and the inner boundary condition. The research is broadly connected to gravitational wave astrophysics, supermassive black holes, and formation of stars and planets. The goals of this thesis are: - learn about astrophysical disks - summarize knowledge on circumbinary disks - literature review on the "lump" - setup a minimal 2D hydrodynamical simulation that exhibits the "lump". Alternatively, modify/simplify an existing setup. - investigate properties of the lump as a function of central binary and inner boundary condition (accretion, mass injection, non-axisymmetric perturbation) |
| References |
| https://ui.adsabs.harvard.edu/abs/2014ApJ...788...22P/abstract
https://ui.adsabs.harvard.edu/abs/2016MNRAS.455.4351P/abstract https://ui.adsabs.harvard.edu/abs/2017ApJ...850...59P/abstract https://ui.adsabs.harvard.edu/abs/2023A%26A...674A.121G/abstract https://ui.adsabs.harvard.edu/abs/2020ApJ...901...25D/abstract https://ui.adsabs.harvard.edu/abs/2016MNRAS.459.2379D/abstract |
| Preliminary scope of work |
| http://utf.mff.cuni.cz/~pejcha/ |