Don Summers

Scheme for Ionization Cooling for a Muon Collider

We discuss a complete scheme for production and cooling a muo n beam for three specified Muon Colliders. We outline the parameters for these Muon Collide rs. The scheme starts with the front end of a proposed Neutrino Factory that yields bunch tr ains of both muon signs. Emittance exchange cooling in upward or downward broad helical lattic es reduces the longitudinal emittance until it becomes possible to merge the trains into single bun ches: one of each sign. Further cooling in all dimensions is applied to the single bunches in further upward climbing helical lattices. Final transverse cooling to the required parameters is achi eved in 50 T solenoids that use high temperature superconductor. Preliminary simulations of e ach element are presented. We discuss known challenges.

A Pulsed Synchrotron for Muon Acceleration at a Neutrino Factory

A 4600 Hz pulsed synchrotron is considered as a means of accelerating cool muons with superconducting RF cavities from 4 to 20 GeV/c for a neutrino factory. Eddy current losses are held to less than a megawatt by the low machine duty cycle plus 100 micron thick grain oriented silicon steel laminations and 250 micron diameter copper wires. Combined function magnets with 20 T/m gradients alternating within single magnets form the lattice. Muon survival is 83%.

Cooling for a High Luminosity 100 TeV Proton Antiproton Collider

A 10³⁴ luminosity 100 TeV proton-antiproton collider is explored. The cross section for many high mass states is 10x higher in p-pbar than p-p collisions. Antiquarks for production can come directly from an antiproton rather than indirectly from gluon splitting. The higher cross sections reduce the synchrotron radiation in superconducting magnets and the vacuum system, because lower beam currents can produce the same rare event rates. Events are also more central, allowing a shorter detector with less space between quadrupole triplets and a smaller beta twiss for higher luminosity. To keep up with the antiproton burn rate, a Fermilab-like antiproton source would be adapted to disperse the beam into 12 different momentum channels, using electrostatic septa, to increase antiproton momentum capture 12x. At Fermilab, antiprotons were stochastically cooled in one debuncher and one accumulator ring. Because the stochastic cooling time scales as the number of particles, 12 independent cooling systems would be used, each one with one debuncher/momentum equalizer ring and two accumulator rings. One electron cooling ring would follow the stochastic cooling rings. Finally antiprotons in the collider ring would be recycled during runs without leaving the collider ring, by joining them to new bunches with snap bunch coalescence and longitudinal synchrotron damping.