Measurements of electron energy probability functions in helicon discharge by laser Thomson scattering

We reported the measurements of electron energy probability functions (EEPFs) in helicon discharge using laser Thomson scattering (LTS). A problematic effect in the measurement, the measured signal intensity in the ICCD camera is influenced by the magnetic field of helicon discharge and measurement time, was carefully addressed through this paper. To solve this problem, we proposed a data processing method of LTS named as normalization method in this paper with the justification of application to our helicon discharge. The measured EEPFs showed clear Maxwellian distributions at various conditions (magnetic fields and RF powers) in elastic collision range.