Model PPC40

Plane-Parallel Ionization Chamber

The Model PPC40 plane-parallel ionization chamber is similar to one developed by Dr. Roos for use as a reference chamber for electron dosimetry.  The outstanding feature of this chamber is a wide guard ring to exclude any perturbation effect even at low electron energies.  The polarity effect also is negligible: less than 1% for all usable energies, field sizes and depths.  The energy dependence is only influenced by the stopping power correction; a type-dependent correction is not necessary.

The chamber is watertight for use in water phantoms.  The measuring volume is vented to the atmosphere through the connecting cable sheath.  The entrance window is flush with the surface so that it can be used with solid phantoms.  The external dimensions conform to the Roos® design.

The PPC40 features a 1.4 meter cable and can be delivered with either a triaxial BNC or TNC connector.

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