Publications In Preparation » History » Revision 15
Preliminary results prepared for presentation at conferences¶
Study of Ionization Cooling with the MICE Experiment (Preliminary)¶
The international Muon Ionization Cooling Experiment (MICE) will demonstrate the ionization cooling of muons; the only known technique that can provide high brightness muon beams suitable for applications such as a Neutrino Factory or Muon Collider. MICE is underway at the Rutherford Appleton Laboratory and has recently taken the data necessary to characterise the physical processes that underlie the ionization-cooling effect. Measurements of the change in normalised transverse amplitude are presented in two configurations. The measurements of the ionization-cooling effect are discussed.
Multiple Coulomb Scattering in Lithium Hydride Absorbers (Preliminary)¶
Multiple coulomb scattering is a well known electromagnetic phenomenon experienced by charged particles traversing materials. However, from recent measurements by the MuScat experiment it is known that the available simulation codes, specifically GEANT4, overestimate the scattering of muons in low Z materials. This is of particular interest to the Muon Ionization Cooling Experiment (MICE) which has the goal of measuring the reduction of a muon beam emittance induced by energy loss in low Z absorbers. Multiple scattering induces positive changes in the emittance in contrast to the reduction due to ionization energy loss. It therefore is essential that MICE measures multiple scattering for its absorber materials; lithium hydride and liquid hydrogen; and validate the multiple scattering against known simulations. MICE took data with magnetic fields off suitable for multiple scattering measurements in the spring of 2016.
Energy Loss in Lithium Hydride and Hydrogen Absorbers (Preliminary)¶
The cooling term of the ionization cooling equation is given by the "Bethe equation". A better understanding of the equation in hydrogen and lithium hydride is necessary in order to make more realistic predictions of the emittance reduction.
Data has been taken for several different muon beams traversing the lithium hydride absorber.
MICE measures the momentum upstream and downstream of the absorber using information from the trackers combined with measurements of the time of flight.
Emittance Exchange in MICE¶
The Muon Ionization Cooling Experiment, MICE, has demonstrated transverse emittance reduction through ionization cooling. Transverse ionization cooling can be used either to prepare a beam for acceleration in a neutrino factory or for the initial stages of beam cooling in a muon collider. Later stages of ionization cooling in the muon collider require the longitudinal emittance to be manipulated using emittance exchange and reverse emittance exchange, where emittance is exchanged from and to longitudinal phase space respectively. A wedge absorber within the MICE cooling channel has been used to experimentally demonstrate reverse emittance exchange in ionization cooling. Parameters for this test have been explored in simulation and applied to experimental configurations using a wedge absorber when collecting data in the MICE beam. This analysis of reverse emittance exchange is presented in detail.