Hohl, MarkusMarkusHohlWurz, PeterPeterWurz0000-0002-2603-1169Bochsler, PeterPeterBochsler2024-10-052024-10-052005https://boris-portal.unibe.ch/handle/20.500.12422/56390X-ray measurements of the plasma of a compact 2.45 GHz electron cyclotron resonance ion source (ECRIS) are performed to determine the temperature and density of the electrons heated resonantly in the ECRIS. The x-ray detector used to investigate the plasma consists of a small silicon (Si-PIN) photodiode to detect photons in the energy range of 1–100 keV. The detector has an energy resolution of 180 eV at 5.9 keV that allows us to record detailed x-ray spectra. Assuming two temperature electron populations, both Maxwellian distributed, the analysis of the x-ray spectra shows a temperature of about 2 keV for the hot electron fraction in addition to the population of cold electrons at less than 2 eV. The fraction of the hot electrons amounts to 1–10%. We present a description of the x-ray detector set-up as well as x-ray spectra and calculations for the temperature and density of the electrons in the ECRIS plasma.en500 - Science::520 - Astronomy600 - Technology::620 - Engineeringarticle10.7892/boris.15343710.1088/0963-0252/14/4/008