The international Muon Ionization Cooling Experiment (MICE), which is under construction at the Rutherford Appleton Laboratory (RAL), will demonstrate the principle of ionization cooling as a technique for the reduction of the phase-space volume occupied by a muon beam. Ionization cooling channels are required for the Neutrino Factory and the Muon Collider. MICE will evaluate in detail the performance of a single lattice cell of the Feasibility Study 2 cooling channel. The MICE Muon Beam has been constructed at the ISIS synchrotron at RAL, and in MICE Step I, it has been characterized using the MICE beam-instrumentation system. In this paper, the MICE Muon Beam and beam-line instrumentation are described. The muon rate is presented as a function of the beam loss generated by the MICE target dipping into the ISIS proton beam. For a 1 V signal from the ISIS beam-loss monitors downstream of our target we obtain a 30 KHz instantaneous muon rate, with a neglible pion contamination in the beam.

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Atmospheric pressure plasma jets (APPJs) have potential applications in many aspects ranging from traditional surface treatment to growing biomedicine. An array structure of such APPJs is the most efficient way to enlarge the treatment area. Nevertheless, the majority of APPJ arrays have shown mottled patterns downstream, a disadvantage for applications. Particularly, in biomedicine and certain other areas, improving the plasma homogeneity downstream of APPJ arrays is crucially needed. In this work, we numerically study synergistic effects of APPJ arrays on plasma propagation and homogeneity downstream based on a model coupling electric, flow, and temperature fields. Taking a two-dimensional three-tube APPJ array as an example, we study the influence of gas velocity and component, as well as applied voltages on plasma distributions. In addition, essential strategies for merging plasma bullets are acquired. Results show that the ionization rate between adjacent jets is important to provide electrons for jet merging. The helium mole fraction controls the plasma distribution and thus directly decides whether adjacent jets merge. After merging, the plasma bullets affect each other through the electric field to control the homogeneity downstream. Therefore, the plasma distribution is a result of the synergy of flow and electric fields. Then, a homogeneous plasma distribution downstream can be realized by the fine control of both fields, which provides an effective way to uniform the plasma downstream in plasma processing.

Abstract-The superconducting coupling solenoid magnet is one of the key equipment in the Muon Ionization Cooling Experiment (MICE). The coil has an inner radius of 750 mm, length of 281 mm and thickness of 104 mm at room temperature. The peak induction in the coil is about 7.3 T with a full current of 210 A. The mechanical disturbances which might cause the instability of the impregnated superconducting magnet involve the frictional motion between conductors and the cracking of impregnated materials. In this paper, the mechanical instability of the superconducting coupling magnet was studied. This paper presents the numerical calculation results of the minimum quench energy (MQE) of the coupling magnet, as well as the dissipated strain energy in the stress concentration region when the epoxy cracks and the frictional energy caused by "stick-slip" of the conductor based on the bending theory of beam happens. Slip planes are used in the coupling coil and the frictional energy due to "slow slip" at the interface of the slip planes was also investigated. The dissipated energy was compared with MQE, and the results show that the cracking of epoxy resin in the region of shear stress concentration is the main factor for premature quench of the coil.