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The Muon Ionization Cooling Experiment (MICE) collaboration has developed the MICE Analysis User Software (MAUS) to simulate and analyze experimental data. It serves as the primary codebase for the experiment, providing for offline batch simulation and reconstruction as well as online data quality checks. The software provides both traditional particle-physics functionalities such as track reconstruction and particle identification, and accelerator physics functions, such as calculating transfer matrices and emittances. The code design is object orientated, but has a top-level structure based on the Map-Reduce model. This allows for parallelization to support live data reconstruction during data-taking operations. MAUS allows users to develop in either Python or C++ and provides APIs for both. Various software engineering practices from industry are also used to ensure correct and maintainable code, including style, unit and integration tests, continuous integration and load testing, code reviews, and distributed version control. The software framework and the simulation and reconstruction capabilities are described.

McCartney makes a valid point about the questionable effectiveness of the flu vaccine, but she provides little substantive evidence of the negative effects of vaccination.1 She quotes the 2016-17 effectiveness of 41% in adults under 65, which would have been sufficient to provide herd immunity in many recent influenza outbreaks …

During magnet commissioning in September 2015, the leads on coil M1 of the downstream spectrometer solenoid failed. The coil will not be operational for MICE Step IV. Revised optics settings for the Step IV data taking are reviewed.

Coherent Smith-Purcell (SP) radiation originating from three different gratings has been measured at End Station A, SLAC, and has been used to reconstruct the time profile of the electron bunches. The beam energy during these experiments was 28.5 GeV ($\ensuremath{\gamma}\ensuremath{\cong}55\text{ }773$) and the number of electrons in the bunch was $0.9--1.4\ifmmode\times\else\texttimes\fi{}{10}^{10}$. The spectral distribution of the radiated energy was measured by means of an array of 11 pyroelectric detectors. Typical values of the FWHM of the bunch length are about 2.5 ps, but sharper peaks with FWHM less than 2.0 ps have also been observed. The longitudinal profile also varies with accelerator conditions and can best be approximated by a superposition of 3--4 Gaussian curves. Some typical profiles are presented, together with a discussion of the limitations and strengths of coherent SP radiation as a diagnostic tool. It is concluded that SP radiation offers excellent prospects in this respect, not only in the picosecond range, but potentially in the femtosecond range as well.

We report some preliminary results of the Smith-Purcell radiation produced by the interaction of the 28.5 GeV electron beam with a ruled grating at the Stanford Linear Accelerator Center (SLAC). The objects of the experiment were to investigate the longitudinal (temporal) profile of the beam and to confirm that the radiated power was in agreement with the predictions of our surface current theory of the emission. The results are compared with those from earlier, lower, electron energy experiments and preliminary analysis indicates that our theoretical approach is valid over more than a four order range of electron energy from ~2 MeV to ~30 GeV.

We report on measurements of picosecond bunch lengths and the energy-z correlation of the bunch with a high energy electron test beam to the A-line and end station A (ESA) facilities at SLAC. The bunch length and the energy-Z correlation of the bunch are measured at the end of the linac using a synchrotron light monitor diagnostic at a high dispersion point in the A-line and a transverse RF deflecting cavity at the end of the linac. Measurements of the bunch length in ESA were made using high frequency diodes (up to 100 GHz) and pyroelectric detectors at a ceramic gap in the beamline. Modelling of the beam's longitudinal phase space through the linac and A-line to ESA is done using the 2-dimensional tracking program LiTrack, and LiTrack simulation results are compared with data. High frequency diode and pyroelectric detectors are planned to be used as part of a bunch length feedback system for the LCLS EEL at SLAC. The LCLS also plans precise bunch length and energy-Z correlation measurements using transverse RF deflecting cavities.

We have used coherent Smith-Purcell radiation in order to investigate the longitudinal (temporal) profile of the electron bunch at the FELIX facility. Detection of the far-infrared radiation was achieved by a simple and compact experimental arrangement, consisting of an array of 11 room-temperature pyroelectric detectors. Accurate determination of the background radiation, use of high quality optical filters, and an efficient light collection system are essential for this type of experiment. The radiated power is in good agreement with the predictions of the surface current description of this process. It is concluded that 90% of the bunch particles are contained within 5.5 ps, with a temporal profile that could be approximately triangular in shape. © 2006 The American Physical Society.