Abstract :
The more beam is cooled, the less stable it is. In the 3.3 km Recycler Ring, stacked 8 GeV antiprotons are cooled both with stochastic (transversely) and electron (3D) cooling. Since the machine is staying near the coupling resonance, coupled optical functions should be used for stability analysis. To stabilize beam against the resistive wall instability, a digital damper is used. Digital dampers can be described as linear operators with explicit time dependence, and that makes a principle difference with analogous dampers. Theoretical description of the digital dampers is presented. Electron cooling makes possible a two-beam instability of the cooled beam with the electron beam. Special features of this instability are described, and the remedy is discussed.
Keywords :
electron beams; particle beam dynamics; particle beam stability; proton beams; storage rings; 3D electron cooling; cooled antiproton beam instabilities; coupled optical functions; digital damper; distance 3.3 km; electron beam; electron volt energy 8 GeV; recycler ring; resistive wall instability; stochastic cooling; two-beam instability; Cooling; Electron beams; Electron optics; Frequency; Magnetic fields; Optical beams; Optical coupling; Optical feedback; Stochastic processes; Virtual manufacturing;
