Cosmic rays are energetic particles (protons and heavier nuclei) that constantly bombard the Earth's atmosphere. Their origin is still unknown, but possible sources of cosmic rays include supernova remnants, gamma-ray bursts and active black holes. To identify the sources, detailed measurements of the cosmic-ray mass, energy and arrival direction are needed. At the astrophysics department of the VUB, a new method is used to infer cosmic-ray masses from the short radio flashes that are emitted when cosmic particles interact in the Earth's atmopshere. These pulses are detected with LOFAR, a revolutionary radio telescope built in the Netherlands. In contrast to traditional dish telescopes, LOFAR can constantly monitor the whole sky, recording cosmic ray radio flashes whenever they occur. The complex radio patterns carry information about the cosmic ray, and will help to better understand and disentangle the Galactic and extragalactic contributions to the cosmic-ray flux.
This research was awarded an ERC Research Grant.