The preparation of particle beams for experiments of hadron physics: Slow extraction at ELFE rate at DESY and ELSA, as well as beam cooling at HERA

Various complementary experimental approaches are possible to study hadron physics, all of which require dedicated accelerator facilities. One approach, known as the ELFE rate at DESY project, makes use of a continuous electron beam with an energy of 15 to 25 GeV, a current of at least 30 μA and very small emittance, for fixed target experiments. The formation of such a beam by stretching a pulsed LINAC beam with the help of the HERA electron ring has been studied. At lower beam energies and currents this concept is already being used at the ELSA facility of Bonn University. Here the extraction process has been studied intensively and has been compared with measurements. Another approach to study hadron physics is the use of an electron - ion collider. To achieve high integrated luminosities cooling of the ion beam is necessary, especially in the case of heavy ions. For HERA high energy beam cooling with the help of an electron storage ring has been studied. (orig.)