Derbenev, Yaroslav | Search NASA

DOE OSTI2021

Plasma Lens in Parametric Resonance Ionization Cooling

We present a concept of a plasma lens in a parametric resonance ionization cooling (PIC) for extra cooling of muon colliders. The PIC concept has been developed to overcome most aberrations. However, parasitic non-linear aberrations which is induced in an ionization cooling material still reduce a dynamic aperture of the PIC. The plasma lens generates an azimuthally symmetric focusing field in gas-filled RF cavities that is several orders of magnitude stronger than the conventional superconducting magnets. It allows for reduction of the beam size at the beam expansion points. This reduces the size of the aberrations and therefore greatly simplifies their compensation.

43 PARTICLE ACCELERATORS↗

DOE OSTI2020

High Energy ERLs for Electron Cooling

Future electron-ion colliders such as the recently approved eRHIC collide high-intensity ion beams with high current electron beams. The electron beams take advantage of synchrotron radiation to damp emittances but the ion beams must be cooled via some beam-cooling mechanism, including electron cooling. The ion energies are typically a few hundreds of GeV per nucleon. At this energy, a DC cooler powered by an electrostatic accelerator, the preferred cooling approach on existing machines, is not feasible. An ERL, in principle, can provide the high current and brightness to cool these high-brightness ion beams. The beam quality requirements are much different from previous ERLs designs used for FELs. The cooling bunch must be very long to match the ion beam and the relative energy spread must be very small. Incoherent cooling can be enhanced with magnetized beams, but the magnetization must be maintained throughout the ERL. An alternate cooling mechanism, the so-called Coherent Electron Cooling, is, in principle, stronger and can be done with non-magnetized beams. We will present two applications of an ERL to high energy electron cooling and describe some of the technical challenges that must be overcome to operate such an ERL

Benson, Stephen↗