Measurement of negative ion density near the plasma grid by photodetachment
- Department of Electronics, Doshisha University, Tanabe, Kyoto, 610-03 (Japan)
The density of negative hydrogen ions (H{sup {minus}}) near the plasma grid of a Cs introduced H{sup {minus}} source has been measured with the photodetachment method. Addition of Cs into the discharge had increased photodetachment signal, but the time constant of the photodetachment signal had been enlarged as the amount of Cs had been increased. Desorption of Cs on the probe surface by the laser irradiation seems to cause the apparent photodetachment signal. To avoid the effect of laser induced Cs desorption, the temporal increase of an electron current extracted through a hole of the plasma grid was measured by injecting a laser light in the region near the extraction hole. The detected current showed an increase as Cs was added to the discharge. {copyright} {ital 1996 American Institute of Physics.}
- OSTI ID:
- 451339
- Report Number(s):
- CONF-9510304--
- Journal Information:
- AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 380; ISSN 0094-243X; ISSN APCPCS
- Country of Publication:
- United States
- Language:
- English
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