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The Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) at CERN aims to develop a proof-of-principle electron accelerator based on proton driven plasma wake-field acceleration. The core of AWAKE is a 10 metre long plasma cell filled with Rubidium vapour in which single, 400 GeV, proton bunches extracted from the CERN Super Proton Synchrotron (SPS) generate a strong plasma wakefield. The plasma is seeded using a femtosecond pulsed Ti:Sapphire laser. The aim of the experiment is to inject low energy electrons onto the plasma wake and accelerate them over this short distance to an energy of several GeV. To achieve its commissioning goals, AWAKE requires the precise measurement of the position and transverse profile of the laser, proton and electron beams as well as their temporal synchronisation. This contribution will present the beam instrumentation systems designed for AWAKE and their performance during the 2016 proton beam commissioning period., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

This paper presents the design on the Cornell Electron Storage Ring (CESR) of an experimental set-up to meas-ure incoherent Diffraction Cherenkov Radiation (DChR) produced in a 2 cm long SiO2 radiator by a 2.1 GeV elec-tron beam. The electron beam is circulating at a distance of few mm from the edge of the radiator and the DChR photon output power is expected to be significantly higher than the diffraction radiation power emitted from a metal-lic slit of similar aperture. The radiator design and the detection set-up are presented in detail together with sim-ulations describing the expected properties of the emitted DChR in terms of light intensity and spectral bandwidth. Finally, potential applications of DChR are discussed., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The majority of optical diagnostics currently used will not stand up to the requirements of the next generation of particle accelerators. Current methodologies need innovation to be able to reach the sub-micrometre resolution and sensitivity that will be required. One technique that has the potential to meet these requirements is optical transition radiation (OTR) imaging. A new algorithm is proposed which incorporates OTR theory, optical effects and beam distribution. This algorithm takes an existing method used for beam imaging and pushes the limits resolution beyond that normally attainable. In doing so, it can provide a reliable and economical diagnostic for future accelerators. A discussion on further applications of the algorithm is also presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Any imaging system requires the use of various optical components to transfer the light from the source, e.g. optical radiation generated by a charged particle beam, to the sensor. The impact of the transfer optics on the image resolution is often not well known. To improve this situation, the point spread function (PSF) of the optical system must be measured, preferably, with high dynamic range. For this purpose we have created an intense, small (~ 1 μm) point source using a high quality laser and special focusing optics; and introduced a digital micro-mirror array in the optical system to substantially increase its dynamic range. The PSFs of optical systems that are currently being developed for high resolution, high dynamic range beam imaging using optical transition and diffraction radiation are measured and compared to Zemax simulations. The goal of these studies is to systematically understand and mitigate any ill effects on the PSF due to aberrations, diffraction and misalignment of the components of the imaging system. We present the results of our measurements and simulations., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The Diode ORbit and OScillation System (DOROS) system is designed to provide accurate measurements of the beam position in the LHC. The oscillation part of the system, which is able to provide turn-by-turn data, is used to measure the transverse coupling. Since the system provides high resolution measurements for many turns only small excitations are needed to accurately measure the transverse coupling. In this article we present the performance the system to measure coupling and compare it to the BPMs not equipped with this system., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The LHC Schottky system allows the measurement of beam parameters such as tune and chromaticity in an entirely non-invasive way by extracting information from the statistical fluctuations in the incoherent motion of particles. The system was commissioned in 2011 and provided satisfactory beam-parameter measurements during LHC run 1 for lead-ions. However, for protons its usability was substantially limited due to strong interfering signals originating from the coherent motion of the particle bunch. The system has recently been upgraded with optimized travelling-wave pick-ups and an improved 4.8~GHz microwave signal path, with the front-end and the triple down-mixing chain optimized to reduce coherent signals. Design and operational aspects for the complete system are shown and the results from measurements with LHC beams in Run II are presented and discussed., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

Next generation linear colliders such as the Compact Linear Collider (CLIC) or the International Linear Collider (ILC) will accelerate particle beams with extremely small emittance. The high current and small size of the beam (micron-scale) due to such small emittance require non-invasive, high-resolution techniques for beam diagnostics. Diffraction Radiation (DR), a polarization radiation that appears when a charged particle moves in the vicinity of a medium, is an ideal candidate being non-invasive and allowing beams as small as a few tens of microns to be measured. Since DR is sensitive to beam parameters other than the transverse profile (e.g. its divergence and position), preparatory simulations have been performed with realistic beam parameters. A new dedicated instrument was installed in the KEK-ATF2 beam line in February 2016. At present DR is observed in the visible wavelength range, with an upgrade to the ultraviolet (200nm) planned for spring 2017 to optimize sensitivity to smaller beam sizes. Presented here are the latest results of these DR beam size measurements and simulations., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark