BEAM DYNAMICS SIMULATION IN HIGH ENERGY ELECTRON COOLER

The article deals with electron beam dynamics in projected high energy electron cooler. Classical electrostatic scheme with several MeV electron energy is considered. The increase of transversal energy of electrons in an accelerating section, in bends and at the matching point of magnetic fields is calculated. In order to calculate beam behaviour in bends with electrostatic compensation of centripetal drift new ELEC3D electroand magnitostatic 3D code is developed. BEAM code is used for simulation of dynamics in an accelerating section. The methods of keeping low transversal energy are estimated. HESR ELECTRON COOLER The subject of the article is the investigation of the electron beam dynamics in high energy electron cooler. Fast electron cooling of antiproton beams in the energy range between 0.8 and 14.5 GeV is a key feature for one of the major objectives of the GSI future plans: internal target experiments at the High Energy Storage Ring HESR [1]. The powerful cooling is required for the high resolution experiments investigating the structure of hadrons and the interaction of quarks and gluons in the nuclear medium. The project of 8 MeV electron cooler proposed by BINP is based on classical electrostatic scheme. The electrostatic column is 8 m high; it consists of a number of sections with a potential growing from the bottom section to the top one. The insulating gas is SF6 being under pressure to ensure the desirable electric strength. The electrostatic column has three accelerating tubes, two tubes for the acceleration and deceleration of an electron beam, and one for the charging of the column head. For the electrostatic cooler a small cyclotron for 10 MeV H ions as a charging system is proposed. Accelerated electron beam is bent in the vertical and horizontal planes and is moved to the cooling section. After the main solenoid the beam is returned to the electrostatic column, where it is decelerated to recuperate its energy. Longitudinal magnetic field accompanies electron beam along all its way.