Remote sensing of high energy charged particle current (HEC) for megavoltage therapeutic electron beams

<i>Objective.</i>We demonstrate detection of high energy particle current (HEC) for MeV therapeutic electron beams. Detection of HEC comprises of remote sensing or acquiring information about HEC inside radiation transport medium from a distance outside of the medium.<i>Approach.</i>HEC is self-propelled motion of charged particles through a radiation transport medium. Remote sensing of HEC is embodied in an experimental setup, which includes homogeneous and heterogeneous phantoms irradiated with 4-15 MeV electron beams and two large area parallel-plane electrodes extraneous to the phantoms providing two-parameter detection. We also introduce a new type of scanning method (depth-scan) for probing object properties along the beamline axis.<i>Main Results.</i>Deterministic radiation transport simulations and measurements agree, considering differences in simulation vs experimental geometry and experimental uncertainties.<i>Significance.</i>This method may be suitable for range detection of charged particle beams, or for probing of radiation opaque objects in non-destructive testing.