It is known that the magnetic fields of white dwarfs can be a million times stronger than that of Earth. Research led by the Nucleus Millennium of Planetary Formation (NPF) Director Matthias Schreiber showed in 2021 that a dynamo mechanism similar to the one that generates magnetic fields on Earth and the other planets can work in white dwarfs, and produce much stronger fields. This research was published in the prestigious scientific journal Nature Astronomy.
In new research, Schreiber, together with an international team of astrophysicists, shows that the model also works to explain the magnetic fields observed in white dwarfs in double systems, i.e. binaries of two white dwarfs. This was also proven for white dwarfs that receive planetary material.
This model, indicates the astrophysicist – who is also an academic at Santa Maria University – results from an analogy of the internal structure of white dwarfs and planets, and was performed using the 2021 model for magnetic fields together with models of stellar evolution. “This shows that the proposed 2021 model works in many cases and also highlights the importance of interdisciplinary NPF research,” he stresses.
The next steps of this research are to look for independent evidence for the model, for example by measuring rotation rates of white dwarfs with metal lines. This study is currently being carried out by Martin Chavarria, an NPF undergraduate student working with Schreiber at Universidad Santa María.
Image credit: NASA