On the origin of cosmic-ray electrons

Abstract

The writer has been the last student who graduated with Beppo few years before his retirement. His thesis: “The energy spectrum of cosmic-ray electrons (CRE)” [1] was inspired by Beppo’s obsession for the origin of CRs. The thesis was focused on the calculation of the diffusion equation that could account for all forms of energy losses suffered by electrons in their interstellar journey, aimed at constraining the primary electron spectrum from the spectrum observed within the solar cavity. The idea was to find observational constraints to models of CR acceleration by supernovae and their remnants. CRE and radio astronomy are adjacent fields of research because CRE lose energy via the synchrotron mechanism on galactic magnetic fields, producing radio waves. So, even when I eventually became a radio astronomer at the Leiden Sterrewacht, working on radio galaxies, I kept wondering about the origin of cosmic rays.