IIT, Chicago, Illinois, USA
Fermilab, Batavia, Illinois, USA
University of Chicago, Chicago, Illinois, USA
BNL, Upton, Long Island, New York, USA
Ionization cooling is the preferred method of cooling a muon beam for the purposes of a bright muon source. This process works by sending a muon beam through an absorbing material and replacing the lost longitudinal momentum with radio frequency (RF) cavities. To maximize the effect of cooling, a small optical beta function is required at the locations of the absorbers. Strong focusing is therefore required, and as a result normal conducting RF cavities must operate in external magnetic fields on the order of 10 Tesla. Vacuum and high pressure gas filled RF test cells have been studied at the MuCool Test Area at Fermilab. Methods for mitigating breakdown in both test cells, as well as the effect of plasma loading in the gas filled test cell have been investigated. The results of these tests, as well as the current status of the two leading muon cooling channel designs, will be presented.
THYAUD03
BNL, Upton, Long Island, New York, USA
Generation of bright muon sources requires a reduction of the six-dimensional emittance of the captured muon beam by several orders of magnitude. In this study, we present a new cooling scheme that should meet this requirement. First, we present the conceptual design of our proposed scheme wherein we detail its basic features. Then, we present the first end-to-end simulation of 6D cooling for a Muon Collider and show a notable reduction of the 6D emittance by five orders of magnitude. Finally, we examine the influence of space-charge fields on the cooling process and present a space-charge compensation solution by means of increasing the rf gradient. We establish a quantitative relationship between the required compensation gradient and bunch charge.