Ionization Chambers

We have the capabilities to produce custom ionization chamber assemblies within the following specifications:

• detection electrodes: gold-coated polyimide foils (down to 25 µm polyimide foil thickness and up to 1 µm gold coating)
• optional structuring of the coating: strips for beam position measurement with down to 0.8 mm strip width and 1.0 mm periodicity
• sensitive area: up to 450 mm x 550 mm
• electrode gap distance: down to 1.0 mm
• applicable electrical field strength between electrodes: up to 600 V/mm (at lowest dark currents in pA range)

Our Ionization Chamber assemblies might house multiple beam monitors as well as additional sensors (e.g. temperature sensor), can be sealed against ambient atmosphere (with dust-filtered air inlet for ambient air ICs) and operation is invariant against chamber orientation (proofen angle independent operation in clinical gantries).

The Varian ProBeam nozzle ionization chamber is based on our technology and is proven to be capable of correctly handling even FLASH proton beams, see [1].

Reference: [1] "Beam Diagnostics for Flash RT in the Varian ProBeam System", M. Schedler, S. Busold, M. Bräuer, IPAC 2022