Ar-Ar Lab
3) Mass spectrometer (MAP-215)

Back to purification line (stepwise heating technique)...
Back to laser extraction line...

Gas arriving from extraction line (on the left on the picture) is sent in mass spectrometer. Naturally, at this moment the ionic pump valve (for vacuum inside spectrometer) is closed... Gas is ionized and then sent through magnet field. This one deviate ions according to their ratio mass on charge. Each argon masses (36 to 40) is measured by placing a collector (a Faraday cup, see scheme of the line) at the position of mass to measure. According to the type of spectrometer, there is only one collector (as in Berne) or more (multicollector system) allowing simultaneous measurement of all argon masses. In our case, only one Faraday cup is available and we therefore have to change magnet setting to select a specific mass. For more informations on Argon method and mass spectrometers, see my link pages.

Towards countin system...

Back to purification line (stepwise heating technique)...
Back to laser extraction line...

Gas arriving from extraction line (on the left on the picture) is sent in mass spectrometer. Naturally, at this moment the ionic pump valve (for vacuum inside spectrometer) is closed... Gas is ionized and then sent through magnet field. This one deviate ions according to their ratio mass on charge. Each argon masses (36 to 40) is measured by placing a collector (a Faraday cup, see scheme of the line) at the position of mass to measure. According to the type of spectrometer, there is only one collector (as in Berne) or more (multicollector system) allowing simultaneous measurement of all argon masses. In our case, only one Faraday cup is available and we therefore have to change magnet setting to select a specific mass. For more informations on Argon method and mass spectrometers, see my link pages.

Towards countin system...