The principle of muon ionization cooling is to slow down the muons in a light absorber and then reaccelerate them in the beam direction using RF cavities. In MICE, the entire system is inserted inside a magnetic channel in order to better contain the beam.
MICE setup includes 3 liquid hydrogen absorbers and 2 RF cavities units. This should be enough to reduce the emittance of the 200 MeV muon beam by 10 %.
Here is a nice PowerPoint presentation of the Cooling Channel.
addition, several particle detectors are used in order to detect, identify and
and measure precisely the momentum of each muon from the beam. Two spectrometers
of very similar design, one upstream and one downstream of the cooling section,
provide high-resolution measurement of the five parameters of the muon helix in
embedded in a 4 T solenoid, as well as a precise time measurement. In addition, for muon/pion/electron identification purposes, a t0 timing station and a small Cherenkov are situated in front of the upstream detector and a larger Cherenkov and an EM-Calorimeter are situated beyond the downstream spectrometer.
Even though there are many particle physicists involved, MICE is before all an accelerator physics experiment. From the point of view of the accelerator physicist, all the particle detectors around the cooling unit are just beam diagnostic tools. However, the requirements on the precision of the momentum measurement, on the purity of the particle identification and on the data acquisition rate capability are very challenging and deserve careful attention.The precision required on the measurement of the emittance of the beam before and after the cavities is of the order of 10-3. Such unprecedented accuracy can only be achieved by single particle analysis.
The production of some MICE key elements is already well advance. Here is a small photo album of some of our recent jewels.
|MICE first RF Cavity|
|The first Be Window for the cavity|
|MICE very first absorber|
|First prototype of the MICE Target holder|