I am interested in the general field of stellar astrophysics and extrasolar planets, in particular I like to investigate the following topics:
I have worked on both observational and simulated data. The combination of both approaches is important to gain a complete view on what is happening in such regions.
- early stages of star formation in filaments
- radiative transfer, MonteCarlo
- dust and astrochemistry
- fragmentation of filaments
I have worked on both observational and simulated data. The combination of both approaches is important to gain a complete view on what is happening in such regions.
I investigated how filaments fragment into star-forming cores and which mechanisms cause this behaviour. I used filaments that have formed within the 3D FLASH AMR simulations by Ibañez-Mejiá et al. (2016, 2017). The simulations model a self-gravitating, magnetised, stratified, supernova-driven interstellar medium, including photoelectric heating and radiative cooling. I followed the evolution of three highly resolved molecular clouds that form filamentary structures self-consistently for up to six Myr after self-gravity has been activated in the simulations.
I found that the filaments fragment early in their evolution while they are still thermally stable, meaning that their line masses are below the critical value predicted by the analytic models by Ostriker (1964). More details are given in the paper by Chira et al. (2018).
Lately, I was analysing the turbulent structures within the three model clouds and the filaments they contain. The early on-set of fragmentation suggests that the fragments are formed due to compressive, colliding flows within the filaments and stabilised by accretion of gas that falls perpendicularly onto the filaments.
In the years before, I focused more on the role radiative transfer and how it helps us to connect observations and simulations. For this, I extended and used the 3D MonteCarlo dust radiative transfer code by my ESO advisor Ralf Siebenmorgen. I investigated how the dust emission of pre-stellar filaments changes depending on the viewing angle a filament is observed at.