Texas A&M University, College Station, USA
HiTek ESE LLC, Madison, USA
Fermilab, Batavia, Illinois, USA
LLNL, Livermore, California, USA
The strong-focusing cyclotron is an isochronous sector cyclotron in which slot-geometry superconducting half-cell cavities are used to provide sufficient energy gain per turn to fully separate orbits and superconducting quadrupoles are located in the aperture of each sector dipole to provide strong focusing and control betatron tune. The SFC offers the possibility to address the several effects that most limit beam current in a CW cyclotron: space charge, bunch-bunch interactions, resonance-crossing, and wake fields. Simulation of optical transport and beam dynamics entails several new challenges: the combined-function fields in the sectors must be properly treated in a strongly curving geometry, and the strong energy gain induces continuous mixing of horizontal betatron and synchrotron phase space. We present a systematic simulation of optical transport using modified versions of MAD-X and SYNERGIA. We report progress in introducing further elements that will set the stage for studying dynamics of high-current bunches.
Fermilab, Batavia, Illinois, USA
BNL, Upton, Long Island, New York, USA
Northern Illinois University, DeKalb, Illinois, USA
The Muon g-2 experiment at Fermilab aims to measure the anomalous magnetic moment of the muon to a precision of 140 ppb ─ a fourfold improvement over the 540 ppb precision obtained in BNL experiment E821. Obtaining this precision requires controlling total systematic errors at the 100 ppb level. One form of systematic error on the measurement of the anomalous magnetic moment occurs when the muon beam injected and stored in the ring has a correlation between the muon's spin direction and its momentum. In this paper, we first analyze the creation and transport of muon polarization from the production target to the Muon g-2 storage ring. Then, we detail the spin-momentum and spin-orbit correlations and estimate their impact on the final measurement. Finally, we outline mitigation strategies that could potentially circumvent this problem.