discovered_01_2013

discovered 01.13 FOCUS WWW.Hzdr.DE The photoelectric effect was first described back in the 19th century and no other than Albert Einstein himself offered a theoretical explanation for it in 1905: When a particle of light has sufficient energy, it is able to knock electrons out of an atom. Yet the most popular physicist of all time could scarcely have imagined how the photoelectric effect would one day prompt the development of large-scale scientific facilities, like ELBE – the Electron Linear Accelerator for Radiation of High Brilliance and Low Emittance – one of the Helmholtz-Zentrum Dresden-Rossendorf’s pillars. Here’s how ELBE works: Initially, laser light shoots electrons out from a semiconductor and accelerates them to almost the speed of light by exposing them to very strong electric fields. Next, the electrons start to emit different forms of radiation, from positrons and neutrons to infrared light and gamma rays. And because the electron accelerator is based on superconductor technology, there isn’t any need for a cool-down period. Instead, the facility continuously delivers pulses of a half a billion electrons each within a closely bundled beam, which offers unparalleled research options. // Quanta, antiparticles, neutrons, and more. _TEXT . Roland Knauer THE HEART OF THE ELBE: In an effort to enhance experimental options at the new Center for High-Power Radiation Sources, electron pulses from the electron accelerator that has been in operation for years have to be shortened and intensified by an entire order of magnitude. The electrons are used by the two free electron lasers, two new terahertz sources, as well as for the facilities for the generation of gamma and X-rays, positrons, and neutrons. Photo: Frank Bierstedt The new ELBE

discovered_01_2013

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