FORMATION OF AN ATOMIC-HYDROGEN BEAM BY A HOT CAPILLARY

Citation
Kg. Tschersich et V. Vonbonin, FORMATION OF AN ATOMIC-HYDROGEN BEAM BY A HOT CAPILLARY, Journal of applied physics, 84(8), 1998, pp. 4065-4070
Citations number
34
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics, Applied
Journal title
ISSN journal
0021-8979
Volume
84
Issue
8
Year of publication
1998
Pages
4065 - 4070
Database
ISI
SICI code
0021-8979(1998)84:8<4065:FOAABB>2.0.ZU;2-N
Abstract
A beam of atomic hydrogen is produced by passing hydrogen gas through a tungsten capillary heated to 2600 K by electron impact. By means of a differentially pumped quadrupole mass analyzer the angular distribut ion of the atomic hydrogen is measured for different hydrogen feed pre ssures. The angular distribution is considerably more peaked than a co sine distribution and is narrower the lower the feed pressure is. Base d on the theory of beam formation by molecular flow a simple analytica l model is developed which assumes a spatially limited transparent flo w at the end of the capillary. The measured angular distribution can b e described by the model using the length of transparent flow as the o nly fitting parameter. (C) 1998 American Institute of Physics. [S0021- 8979(98)06420-2].