Studies of Electron Cooling at DESY

Klaus Balewski

Possible options for the future physics program of HERA are electron ion collisions, electron polarized proton collisions or an extension of the current research program with improved quality of the proton beam. For almost all of these options a bright hadron beam is required to achieve a sufficiently high luminosity.  To improve the brightness of the hadron beam the application of electron
cooling is proposed.  A two staged cooling scheme is foreseen. In a first step the hadrons are cooled at medium energy (somewhere between 3 and  20 GeV) and in a second step cooled at the final energy (330 or 820 GeV) mainly to maintain the high beam quality.  At such high energies the application of a standard DC electron cooler is no longer possible and new  cooler concepts have to be developed. For the first step a linac based cooler is used that supplies electron bunches of high beam quality to cool the hadrons and for the second step a storage ring based cooler is foreseen that makes use of the radiation damping of electrons to produce a high quality electron beam. A status report on these two coolers will be given.

Summary