Proefschrift
Galaxy clusters in the decameter sky
Many galaxy clusters exhibit bright diffuse radio emission that traces the underlying structure of the intracluster medium (ICM).
- Auteur
- C. Groeneveld
- Datum
- 05 juni 2025
- Links
- Thesis in Leiden Repository
Determining the properties and uncovering the origin of this diffuse emission is essential for understanding the fundamental physics of the plasma in galaxy clusters. In particular, diffuse emission in galaxy clusters provides unique insights into magnetic fields permeating the ICM, the merger history and the origin of the electron plasma from ancient AGN outbursts.Detecting diffuse radio plasma in a large sample of galaxy clusters requires deep, high-sensitivity observations with sufficient angular resolution to accurately subtract compact sources. This is now feasible thanks to the Low-Frequency Array (LOFAR). In particular, using the low-band antenna (LBA) allows us to find diffuse emission at very low radio frequencies. This thesis presents novel calibration strategies that allow us to reduce LOFAR LBA data at unprecedented low frequencies (between 10-30 MHz), as well as LOFAR LBA data with international baselines.