Photoelectron emission experiments with ECR-driven multi-dipolar negative ion plasma source
Laulainen, J., Kalvas, T., Koivisto, H., Kronholm, R., Tarvainen, O., Aleiferis, S., & Svarnas, P. (2017). Photoelectron emission experiments with ECR-driven multi-dipolar negative ion plasma source. In D. Faircloth (Ed.), NIBS 2016 : Fifth International Symposium on Negative Ions, Beams and Sources (pp. 020012). AIP Conference Proceedings, 1869. AIP Publishing. doi:10.1063/1.4995718
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AIP Conference Proceedings;1869Date
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Copyright © 2017, AIP Publishing LLC. Published in this repository with the kind permission of the publisher.
Photoelectron emission measurements have been performed using a 2.45 GHz ECR-driven multi-dipolar plasma source in a low pressure hydrogen discharge. Photoelectron currents induced by light emitted from ECR zone and H− production region are measured from Al, Cu, Mo, Ta, and stainless steel (SAE 304) surfaces as a function of microwave power and neutral hydrogen pressure. The total photoelectron current from the plasma chamber wall is estimated to reach values up to 1 A for 900 W of injected microwave power. It is concluded that the volumetric photon emission rate in wavelength range relevant for photoelectron emission is a few times higher in arc discharge.