(from the article `electron tube`) ...electrons, electrons within the material may acquire sufficient kinetic energy to be emitted from the surface. The bombarding electrons are called ... Found on http://www.britannica.com/eb/a-z/s/55
<microscopy> Produced by an incident electron passing near an atom in the specimen, near enough to impart some of its energy to a lower energy electron (usually in the K-shell). This causes a slight energy loss and path change in the incident electron and the ionisation of the electron in the specimen atom. This ionised electron then leaves t... Found on http://www.encyclo.co.uk/local/20973