09.05.2025
A recent study by our scientist Kevin Schoeffler, together with his colleagues Nitin Shukla (CINECA High-Performance Computing Department, Italy), and Luis Silva (Universidade de Lisboa, Portugal), has set a strong upper bound on long-range dark matter interactions through plasma physics. The research explores the intriguing possibility that dark matter could be charged under a unique “dark electromagnetism” (dark-EM), causing it to behave like a cold collisionless plasma.
Using advanced simulations, the team discovered that plasma instabilities could lead to significant slowdowns in dark matter dynamics.
Interestingly, astronomical observations of colliding galaxy clusters like the so-called „Bullet Cluster“ only fits to their findings if the interaction strength is extremely weak. As a result, they established a strong upper bound on the dark electromagnetic self-interaction constant.
This new constraint is much stronger than previous limits, suggesting that dark electromagnetic interactions are highly restricted.
This research not only advances our understanding of dark matter but also opens new avenues for further exploration and verification through observational measurements.
Read the full article here:
Can plasma physics establish a significant bound on long-range dark matter interactions?
K. Schoeffler N. Shukla and L. O. Silva, Phys. Rev. D 111, L071701
And please have a look at the popular science article here:
Intergalactic Collision Constrains Dark Electromagnetism
Physics 18, s48
Picture:
Counterstreaming slabs of dark matter plasma, shown in blue, are
slowed down while
interacting with dark magnetic fields, shown in red, which are
generated by kinetic plasma instabilities.
09.04.2025
As part of his PhD project, Sam Taziaux spent two months at the renowned CSIRO Institute in Perth, Australia. There he worked closely with George Heald, head of the SKAO headquarters in Perth, and Alec Thomson, both internationally recognised experts in the field of radio astronomy and the analysis of magnetic fields.
Sam's research project, which is part of A2, is dedicated to analysing cosmic ray transport and magnetic fields in dwarf galaxies. At CSIRO, he was able to benefit from the exceptional expertise there and was able to significantly improve the data reduction and analysis of his observed ATCA and MeerKAT data.
The stay was not only a great professional enhancement for Sam, but also a significant milestone in his scientific career, as he was able to get to know and work with the people from the CSIRO and SKAO. He was also able to establish contacts with the scientist at Curtin University in Perth to exchange ideas and expand his network.
Such research stays are excellent opportunities enabled by the CRC to specifically promote international cooperation. The CRC has thus opened up a unique opportunity to become involved in a global scientific network at an early stage, an invaluable advantage on the path to scientific independence.
Picture: Sam Taziaux and his supervisor Ralf-Jürgen Dettmar at the SKAO regional center at CSIRO, Perth.
11.03.2025
On March 1, 2025, our spokesperson Prof. Julia Tjus became affiliated professor at the Department of Space, Earth and Environment at Chalmers University of Technology in Gothenburg. This honor recognizes her long-standing connection to the Swedish university.
The collaboration is particularly fruitful as Julia’s expertise in high-energy astrophysics perfectly complements the extensive experience of researchers at Chalmers University in measuring and analyzing low-energy radiation.
This synergy allows for deeper insights into extreme cosmic events such as supernova explosions and active galactic nuclei and thus for a better understanding of the origins and properties of cosmic rays.
The aim of the affiliated professorship is to intensify existing collaborations and initiate new projects, especially in connection with the IceCube Neutrino Observatory.
Read more
here and
here
Image: Prof. Susanne Aalto, Professor of Astronomy and Plasma Physics, Deputy President and Deputy CEO of Chalmers University of Technology and Prof. Julia Tjus (right) at Chalmers Campus.
