I am a theoretical and computational astrophysicist. I am mostly interested in the rich phenomena of star formation. I utilize both analytical and numerical tools to answer questions like:
What regulates star formation?
What sets the characteristic mass of stars?
Why are stars clustered?
What determines the properties of stellar binaries?
How is star formation different in other galaxies?
These questions have far reaching implications beyond the field of star formation. The interpretation of observed starlight from any extragalactic sources rely on our understanding and assumptions about star formation. Similarily answering these questions would greatly enhance our knowledge about the circumstances of planet formation.
I am originally from Hungary where I got my bachelor's and master's degrees in physics. I received my PhD in physics from the California Institute of Technology. I am currently a NASA Hubble Fellow at the Center for Astrophysics at Harvard University.
Department of Astronomy
The University of Texas at Austin
2515 Speedway, Stop C1400
Austin, TX 78712 Email:
guszejnov at utexas dot edu
About star formation
Stars are the fundamental pieces of cosmic evolution and their formation is a key process that influences the evolution of galaxies, planets, and the development of life. Despite its importance star formation is not-yet understood. This is because of the wide range of complicated physical processes involved (e.g., gravity, turbulence, magnetic fields, radiation).
We know that stars form in dense clouds of molecular Hydrogen that collapses under its own gravity and form stars of various masses. My goal is to understand the fundamental questions of str formation like: What regulates star formation? What sets the masses of stars? Why are stars clustered? How many stars are born as binaries? How do stars affect the cloud they form in? How is star formation different in other galaxies?
Simulating star formation
I am a lead developer of the STARFORGE collaboration. The STARFORGE suite are the first ever radiation-hydro simulations that follow the evolution of a giant molecular cloud (GMC) throughout its lifetime while also resolving the formation of individual low-mass stars. Such a dynamic range is necessary to investigate how GMC-scale properties influence star formation and how the process may vary in different galactic environments. Such simulations are also necessary to understand how stellar feedback influences gas dynamics in the cloud (e.g., leading to cloud disruption) and how it affects future SF (e.g., changing the IMF or quenching SF). The modular nature of the simulation will allow me to explore the role each physical process plays. For more information and videos see the STARFORGE website and Youtube.
Surface density (left) and line-of-sight velocity dispersion (right) maps of a simulated 20000 solar mass star-forming cloud with radiative feedback.
Analytical models of star formation are useful for understanding the principal mechanisms behind different observed phenomena but are often unable to make quantitative predictions. To study in detail how the different physical processes affect the masses and distribution of stars I developed the MISFIT (MInimalist Star Formation Including Turbulence) semi-analytical framework. Due to its semi-analytical nature MISFIT can simulate a much wider dynamic range than conventional hydro codes: it can follow the evolution of clouds from the scale of giant molecular clouds (10 pc) down to the scales of protostars (0.1 AU). This framework provides a way to explore different star formation models and parameters at a modest computational cost.