The chamber contains a small amount of americium-241, which is an emitter of alpha particles which produce a constant ion current.
Comparison of the ion currents in the two chambers allows compensation for changes due to air pressure, temperature, or the ageing of the source.
An ion current is the influx and/or efflux of ions through an ion channel.
The high electron velocities lead to electron currents much greater than xenon ion currents.
This is to ensure proportionality between the number of original events and the total ion current.
This ion current will differ for different gases at the same pressure; that is, a hot filament ionization gauge is composition-dependent.
The sucrose gap technique allows ion currents to be measured in multicellular tissues.
The SICM can also sample and map the local ion currents above the surface.
The ion current is generated by the creation of "ion pairs".
Neurons and muscle cells create ion currents through their membranes when excited, causing a change in voltage both inside and outside the cell.