Hi guys,

Thank you very much for your suggestions. Unfortunately, this was not the thing I meant, I have to admit my question was not very precise.
 I thought about the pressure dependence while measuring it using a gas mass spectrometer. I found some literature
about noble gases, like.

[1] M. Honda, I. McDougall, D. B. Patterson, A. Doulgeris, and D. A. Clague, “Noble gases in
submarine pillow basalt glasses from Loihi and Kilauea, Hawaii: A solar component in the
Earth,” Geochimica et Cosmochimica Acta, vol. 57, no. 4, pp. 859‐874, 1993.

[2] F. K. A. Burnard P. G., “Calibration of pressure‐dependent sensitivity and discrimination in
Nier‐type noble gas ion sources,” Geochemistry, Geophysics, Geosystems, vol. 1, no. 7.

In these the authors describe, that the ionization efficiency dependes on the gas pressure. Unfortunately, there are no
reasons given why it depends on the pressure.  

Maybe some of you knows why or where to find a reasnoble explanation.


Lukas Flierl
Physikalisch-Technische Bundesanstalt PTB
Metrology in Chemistry, 3.11
Bundesallee 100
38116 Braunschweig, Germany
Tel. +49-531-592-3318
e-mail: [log in to unmask]