MPI, Muenchen, Germany
MPI-P, München, Germany
MPI-P, München, Germany
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
The international Muon Ionisation Cooling Experiment (MICE) is designed to provide a proof of principle of ionisation cooling to reduce the muon beam phase space at a future Neutrino Factory and Muon Collider. The MICE Muon Beam is generated by the decay of pions produced by dipping a cylindrical titanium target into the proton beam of the 800 MeV ISIS synchrotron at the Rutherford Appleton Laboratory, U.K. Studies of the particle rate in the MICE Muon Beamline and its relationship to induced beam loss in ISIS are presented, using data taken in Summer 2010. Using time-of-flight to perform particle identification estimates of muon rates are presented and related to induced beam loss.
JAI, Oxford, United Kingdom
The international Muon Ionization Cooling Experiment (MICE), under construction at the Rutherford Appleton Laboratory in Oxfordshire (UK), is a test of a prototype cooling channel for a future Neutrino Factory. The experiment aims to achieve, using liquid hydrogen absorbers, a 10% reduction in transverse emittance, measured to an accuracy of 1% by two scintillating fibre trackers within 4 T solenoid fields. Step IV of MICE will begin in 2012, producing the experiment's first cooling measurements. Step IV uses an absorber focus coil module, placed between the two trackers, to house liquid hydrogen or solid absorbers. The performance of Step IV using various absorber materials was simulated. Multiple scattering in high Z absorbers was found to mismatch the beam with the lattice optics, which was largely corrected by re-tuning the MICE lattice accordingly.
Oxford University, Physics Department, Oxford, Oxon, United Kingdom
Fermilab, Batavia, USA
Muons, Inc, Batavia, USA
IIT, Chicago, Illinois, USA
Muons, Inc, Batavia, USA
Fermilab, Batavia, USA
Illinois Institute of Technology, Chicago, Illinois, USA
Operating a high gradient radio frequency cavity embedded in a strong magnetic field is an essential requirement for muon beam cooling. However, a magnetic field influences the maximum RF gradient due to focusing of dark current in the RF cavity. This problem is suppressed by filling the RF cavity with dense hydrogen gas. As the next step, we plan to explore the beam loading effect in the high pressure cavity by using a 400 MeV kinetic energy proton beam in the MuCool Test Area at Fermilab. We discuss the experimental setup and instrumentation.
Hampton University, Hampton, Virginia, USA
JLAB, Newport News, Virginia, USA
Muons, Inc, Batavia, USA
Parametric-resonance Ionization Cooling (PIC) is proposed as the final 6D cooling stage of a high-luminosity muon collider. For the implementation of PIC, we earlier developed an epicyclic twin-helix channel with correlated behavior of the horizontal and vertical betatron motions and dispersion. We now insert absorber plates with short energy-recovering units located next to them at the appropriate locations in the twin-helix channel. We first demonstrate conventional ionization cooling in such a system with the optics uncorrelated. We then adjust the correlated optics state and induce a parametric resonance to study ionization cooling under the resonant condition.
IIT, Chicago, Illinois, USA
The Muon Ionization Cooling Experiment (MICE) is a demonstration experiment to prove the viability of cooling a beam of muons for use in a Neutrino Factory and Muon Collider. The MICE cooling channel is a section of a modified Study II cooling channel which will provide a 10% reduction in beam emittance. In order to ensure a reliable measurement, we intend to measure the beam emittance before and after the cooling channel at the level of 1%, or an absolute measurement of 0.001. This renders MICE as a precision experiment which requires strict controls and monitoring of all experimental parameters in order to control systematic errors. The MICE Controls and Monitoring system is based on EPICS and integrates with the DAQ, detector, environment, and data monitoring systems. A description of this system, its implementation, and performance during recent muon beam data collection will be discussed.
Muons, Inc, Batavia, USA
Enrico Fermi Institute, University of Chicago, Chicago, Illinois, USA
A new generation of large-area, low cost time-of-flight detectors with time resolutions ≤ 10 ps and space resolutions ≤ 1 mm is being developed for use in nuclear and particle physics experiments, as well as for medical and industrial applications. Such detectors can serve as the basis for measuring momenta without requiring measurement of curvature in magnetic fields. Factors affecting measurement accuracy and simulation results are presented.
Muons, Inc, Batavia, USA
JLAB, Newport News, Virginia, USA
The Neutrino Factory baseline design involves a complex chain of accelerators including a single-pass linac, two recirculating linacs and an FFAG. The first linac follows the capture and bunching section and accelerates the muons from about 244 to 900 MeV. It must accept a high emittance beam about 30 cm wide with a 10% energy spread. This linac uses counterwound, shielded superconducting solenoids and 201 MHz superconducting cavities. Simulations have been carried out using several codes including Zgoubi, OptiM, GPT, and G4beamline, both to determine the optics and to estimate the radiation loads on the elements due to beam loss and muon decay.
Muons, Inc, Batavia, USA
Old Dominion University, Norfolk, Virginia, USA
LBNL, Berkeley, California, USA
ANL, Argonne, USA
Fermilab, Batavia, USA
Voss Scientific, Albuquerque, New Mexico, USA
Many present and future particle accelerators are limited by the maximum electric gradient and peak surface fields that can be realized in RF cavities. Despite considerable effort, a comprehensive theory of RF breakdown has not been achieved, and mitigation techniques to improve practical maximum accelerating gradients have had only limited success. Recent studies have shown that high gradients can be achieved quickly in 805 MHz RF cavities pressurized with dense hydrogen gas without the need for long conditioning times, because the dense gas can dramatically reduce dark currents and multipacting. In this project we use this high pressure technique to suppress effects of residual gas and geometry found in evacuated cavities to isolate and study the role of the metallic surfaces in RF cavity breakdown as a function of radiofrequency and surface preparation. A 1.3-GHz RF test cell with replaceable electrodes (e.g. Mo, Cu, Be, W, and Nb) has been built, and a series of detailed experiments is planned at the Argonne Wakefield Accelerator. These experiments will be followed by additional experiments using a second test cell operating at 402.5 MHz.
Muons, Inc, Batavia, USA
Fermilab, Batavia, USA
In order to realize a muon collider or a neutrino factory based on a muon storage ring, the muons must be captured and cooled efficiently. For a muon collider, the resulting train of bunches should be coalesced into a single bunch. Design concepts for a system to capture, cool, and coalesce a muon beam are described here. In particular, variants of a helical channel are used, taking advantage of the ability to vary the slip factor and other parameters of such a channel. The cooling application has been described before; this paper reports recent studies of a system that includes two novel concepts to accomplish capture and coalescing via a slip-controlled helical channel.
Northern Illinois University, DeKalb, Illinois, USA
Muons, Inc, Batavia, USA
JLAB, Newport News, Virginia, USA
ODU, Norfolk, Virginia, USA
Tech-X, Boulder, Colorado, USA
UMiss, University, Mississippi, USA
Neutrino factories and muon colliders require significant cooling of the muon beam. Most muon cooling channels are long and expensive single-pass structures, due to the difficulty injecting very large emittance beams into a circular device. Inverse cyclotrons can potentially solve the injection problems associated with other circular cooling channels, and they can potentially provide substantial initial cooling of the beam. We present the first end-to-end (injection to extraction) simulations of an inverse cyclotron for muon cooling, performed with the particle-in-cell code VORPAL. We study the cooling capability of the device as well as potential limitations due to space charge effects and material interactions with the beam.
JLAB, Newport News, Virginia, USA
Muons, Inc, Batavia, USA
BNL, Upton, Long Island, New York, USA
Recirculating Linear Accelerators (RLA) are an efficient way of accelerating short-lived muons to multi-GeV energies required for Neutrino Factories and TeV energies required for Muon Colliders. To reduce the number of required return arcs, we employ a Non-Scaling Fixed-Field Alternating-Gradient (NS-FFAG) arc lattice design. We present a complete linear optics design of a muon RLA with two-pass linear NS-FFAG droplet return arcs. The arcs are composed of symmetric cells with each cell designed using combined function magnets with dipole and quadrupole magnetic field components so that the cell is achromatic and has zero initial and final periodic orbit offsets for both passes’ energies. Matching to the linac is accomplished by adjusting linac quadrupole strengths so that the linac optics on each pass is matched to the arc optics. We adjust the difference of the path lengths and therefore of the times of flight of the two momenta in each arc to ensure proper synchronization with the linac. We investigate the dynamic aperture and momentum acceptance of the arcs.
UCR, Riverside, California, USA
The Muon Ionization Cooling Experiment (MICE) is being built at the ISIS proton synchrotron at Rutherford Appleton Laboratory (RAL) to test ionization cooling of a muon beam. Production of particles in the MICE beamline begins with a titanium target dipping into the ISIS proton beam. The resulting pions are captured, momentum-selected, and fed into a 5T superconducting solenoid. This magnet contains the pions and their decay muons which are then sent through the rest of the MICE beamline toward the cooling channel. During recent data-taking, it was determined that there is a significant background contamination of neutral particles populating the MICE muon beam. This contamination creates unwanted triggers in MICE, thus reducing the percentage of useful data taken during running. This paper describes the analysis done with time-of-flight detectors, used to identify particle type, in order to understand the level of contamination in both positive and negative polarity muon beams.
UCLA, Los Angeles, California, USA
BNL, Upton, Long Island, New York, USA
Particle Beam Lasers, Inc., Northridge, California, USA
A racetrack muon ring cooler for a muon collider is considered. The achromatic cooler uses both dipoles and solenoids. We describe the ring lattice and show the results of beam dynamic simulation that demonstrates a large aperture for acceptance. We also examine the 6D cooling of the muon beam in the cooler and discuss the prospects for the future.
UCLA, Los Angeles, California, USA
BNL, Upton, Long Island, New York, USA
Particle Beam Lasers, Inc., Northridge, California, USA
We present a four-sided ring cooler that employs both dipoles and solenoids to provide robust 6D muon cooling of large emittance beams in order to design and build a muon collider. Our studies show strong 6D cooling adequate for components of a muon collider front end.
UCLA, Los Angeles, California, USA
BNL, Upton, Long Island, New York, USA
It is widely believed that a neutrino factory would deliver unparallel performance in studying neutrino mixing and would provide tremendous sensitivity to new physics in the neutrino sector. Here we will describe and simulate the front-end of the neutrino factory system, which plays critical role in determining the number of muons that can be accepted by the downstream accelerators. In this system, a proton bunch on a target creates secondaries that drift into a capture transport channel. A sequence of rf cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to nearly equal central energies, and initiates ionization cooling. For this, the muon beams are transported through sections containing high-gradient cavities and strong focusing solenoids. In this paper we present results of optimization and variation studies toward obtaining the maximum number of muons for a neutrino factory by using a compact transport channel.
Stratakis et al. Phys. Rev. ST Accel. Beams 14, 011001 (2011).
UCR, Riverside, California, USA
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
The Muon Ionization Cooling Experiment (MICE) will test transverse cooling of a muon beam, satisfying a crucial demonstration step along the path toward creating high intensity muon beams in a Neutrino Factory or Muon Collider. In the last year, MICE has taken a record amount of data to commission the beamline and calibrate the particle identification (PID) detectors. Studies of the MICE beamline and target timing will be discussed, including the use of Time-of-Flight (TOF) detectors to understand the MICE beam content.
IIT, Chicago, Illinois, USA
UCR, Riverside, California, USA
BNL, Upton, Long Island, New York, USA
Recent progress in six-dimensional (6D) cooling simulations for the Muon Collider based on the RFOFO ring layout is presented. In order to improve the performance of the cooling channel a tapering scheme is studied that implies changing the parameters such as cell length, magnetic field strength, RF frequency, and the amount of the absorbing material along the cooling channel. This approach allows us to keep the cooling rates high throughout the process. The results of the simulations carried out in G4beamline are presented.
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
UCR, Riverside, California, USA
IIT, Chicago, Illinois, USA
In the Muon Ionization Cooling Experiment (MICE), muons are cooled by passing through material, then through RF cavities to compensate for the energy loss; which reduces the transverse emittance. It is planned to demonstrate longitudinal emittance reduction via emittance exchange in MICE by using a solid wedge absorber in Step IV. Based on the outcome of previous studies, the shape and material of the wedge were chosen. We address here further simulation efforts for the absorber of choice as well as engineering considerations in connection with the absorber support design.
University of Chicago, Chicago, Illinois, USA
The international Muon Ionization and Cooling Exper- iment (MICE) aims to demonstrate transverse beam emit- tance reduction for a muon beam. During the summer of 2010, data was taken using different configurations of the upstream beam line magnets to measure the optical pa- rameters of the muon beam and study the functionality of the beam line itself. Throughout this period of data taking, reference runs were taken with a fixed target configuration, and magnet settings which provide a muon beam with 200 MeV/c momentum and 6π 4D transverse emittance. Time of flight (TOF) detectors were used to measure many of the beam properties including emittance, particle identifi- cation, and profile. Analysis of these reference runs was carried out in order to determine the stability and repro- ducibility of the beam line data. This overall data quality check is essential to ensure the validity of measurements made so that further analysis can be carried out and that the muon beam is suitable for the MICE cooling channel.
BINP SB RAS, Novosibirsk, Russia
University of Chicago, Chicago, Illinois, USA
LBNL, Berkeley, California, USA
Significant progress has been made in recent years in R&D towards a neutrino factory and muon collider. The U.S. Muon Accelerator Program (MAP) has been formed recently to expedite the R&D efforts. This talk will review the US MAP R&D programs for a neutrino factory and muon collider. Muon ionization cooling research is the key element of the program. The first muon ionization cooling demonstration experiment, MICE (Muon Ionization Cooling Experiment) is under construction now at RAL (Rutherford Appleton Laboratory) in UK. Status of MICE as well as the U.S. contribution to MICE will be presented.
