1) Nanotechnology tool 
stream of electrons (as from a betatron) generated by heat (thermionic emission), bombardment of charged atoms or particles (secondary electron ... [9 related articles]
A stream of electrons (small negatively charged particles found in atoms) that can be used for radiation therapy.
electron flux emitted from one source and moving along the exactly determined tracks with very great velocities
High energy particles which can be used in the treatment of cancer. Electron radiation does not penetrate into tissue as far as x-rays. The beam is therefore useful for treating shallow tumors and tumors in the head and neck where control of depth is essential.
<microscopy> A stream of electrons in an electron optical system. ... (05 Aug 1998) ... 
Type: Term Definitions: 1. a form of radiation used principally in superficial radiotherapy. See: betatron
noun a group of nearly parallel lines of electromagnetic radiation
The stream of electrons generated by the electron gun and accelerated by the accelerator guide.