Abstract: A method and a device for irradiating a confined volume of material, generally situated at a substantial depth below surface, with a beam of high energy charged or uncharged (neutral) particles have a characteristic feature that a beam of charged particles (e.g., electrons, protons, or deuterons) coming from a radiation source is scanned electrically in two orthogonal directions. To obtain a scanned beam of neutral particles, for example photons, a scanned beam of electrons is directed into a target which then emits the scanned beam of neutral particles to be incident into the confined volume. The emerging neutral particles will be emitted from the target predominantly in the direction as the incoming charged particles.