<P> The first video images of an electron's energy distribution were captured by a team at Lund University in Sweden, February 2008 . The scientists used extremely short flashes of light, called attosecond pulses, which allowed an electron's motion to be observed for the first time . </P> <P> The distribution of the electrons in solid materials can be visualized by angle - resolved photoemission spectroscopy (ARPES). This technique employs the photoelectric effect to measure the reciprocal space--a mathematical representation of periodic structures that is used to infer the original structure . ARPES can be used to determine the direction, speed and scattering of electrons within the material . </P> <P> Electron beams are used in welding . They allow energy densities up to 7007100000000000000 ♠ 10 W cm across a narrow focus diameter of 0.1--1.3 mm and usually require no filler material . This welding technique must be performed in a vacuum to prevent the electrons from interacting with the gas before reaching their target, and it can be used to join conductive materials that would otherwise be considered unsuitable for welding . </P> <P> Electron - beam lithography (EBL) is a method of etching semiconductors at resolutions smaller than a micrometer . This technique is limited by high costs, slow performance, the need to operate the beam in the vacuum and the tendency of the electrons to scatter in solids . The last problem limits the resolution to about 10 nm . For this reason, EBL is primarily used for the production of small numbers of specialized integrated circuits . </P>

Who found the actual charge of the electron