Bugnet Group
Asterics – Asteroseismology and Stellar Dynamics
Our understanding of the universe from exoplanets characterization to galactic archaeology strongly relies on our understanding of stellar dynamics. It was recently discovered that stellar evolution models that take into account the rotation of the star and associated hydrodynamic transport processes predict a much faster rotation rate than what is observed. Since then, it is of paramount importance to understand how angular momentum is redistributed inside stars, as it could strongly modify our theory of stellar evolution, and thus the estimation of ages in the universe.
In large part, this turnaround was made possible by Asteroseismology, which then became one of the leading methods for the characterization of stars. This recent branch of stellar physics consists of the analysis of oscillations of stars induced by stationary waves. It is the analogue of seismology on Earth, since it allows to probe the internal structure and the dynamics of the body.
The research activities of the Bugnet group aim at understanding the evolution of stars and their dynamical processes thanks to Asteroseismology. Stellar magnetic fields, from the core to the envelope of the star, are at the center of the group’s research. So far, they have largely been excluded from stellar evolution models due to a lack of observation and of theoretical prescriptions. To make the necessary breakthrough on our understanding of poorly characterized but essential stellar magnetic fields, the group brings together in synergy observational constraints from Asteroseismology, modeling of stellar evolution, and theoretical prescriptions.
Group Leader
Administrative Support
Team
Applications are currently open for PhD and Postdoctoral positions in the Bugnet group at ISTA.
Contact: lisa.bugnet@ista.ac.at
Current Projects
- Detection of magnetic fields in the radiative interior of Solar-like stars
- Magnetic fields at the core/surface boundary
- Impact of the magnetic activity on the excitation of stellar oscillations
- Stellar magnetism across the Hertzsprung-Russell diagram
- Angular momentum transport by magnetism in stellar interiors
- Machine learning for asteroseismology and the PLATO space mission
Publications
Hatt EJ, Ong JMJ, Nielsen MB, Chaplin WJ, Davies GR, Deheuvels S, Ballot J, Li G, Bugnet LA. 2024. Asteroseismic signatures of core magnetism and rotation in hundreds of low-luminosity red giants. Monthly Notices of the Royal Astronomical Society. 534(2), 1060–1076. View
Das SB, Einramhof L, Bugnet LA. 2024. Unveiling complex magnetic field configurations in red giant stars. Astronomy and Astrophysics. 690, A217. View
Bhattacharya S, Das SB, Bugnet LA, Panda S, Hanasoge SM. 2024. Detectability of axisymmetric magnetic fields from the core to the surface of oscillating post-main-sequence stars. Astrophysical Journal. 970(1), 42. View
Mathur S, Claytor ZR, Santos ÂRG, García RA, Amard L, Bugnet LA, Corsaro E, Bonanno A, Breton SN, Godoy-Rivera D, Pinsonneault MH, van Saders J. 2023. Magnetic activity evolution of solar-like stars. I. Sph–age relation derived from Kepler observations. The Astrophysical Journal. 952(2), 131. View
Mathis S, Bugnet LA. 2023. Asymmetries of frequency splittings of dipolar mixed modes: A window on the topology of deep magnetic fields. Astronomy and Astrophysics. 676, L9. View
ReX-Link: Lisa Bugnet
Career
Since 2023 Assistant Professor, Institute of Science and Technology Austria (ISTA)
2020 – 2022 Flatiron Research Fellow, Flatiron Institute, Simons Foundation, New York, USA
2020 PhD, The French Alternative Energies and Atomic Energy Commission (CEA), Paris-Cité University, Paris, France
Selected Distinctions
2021 PhD Prize of the French Society of Astronomy and Astrophysics (SF2A)
2020 PhD Prize of the International Astronomical Union (IAU) – Division G
2020 Flatiron Research Fellowship, Flatiron Institute, USA
2019 “For Women in Science” Young Fellow France, L’Oréal-UNESCO
2019 Best Oral contribution, KASC/TASC conference, Aarhus University, Denmark
