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The PRAE project aims at creating a multidisciplinary R&D facility in the Orsay campus gathering various scientific communities involved in radiobiology, subatomic physics, instrumentation and particle accelerators around an electron accelerator delivering a high-performance beam with energy up to 70 MeV and later 140 MeV, in order to perform a series of unique measurements and future challenging R&D. In addition PRAE will provide a major education and training asset for students and engineers yielding a regional instrument of advanced technology at the heart of the scientific, technological and academic complex of the Paris-Saclay University. In this paper we report the first optics design and performance evaluations of such a multidisciplinary machine, including a first description of future experiments and the required beam instrumentation., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The FCC-hh (Future Hadron-Hadron Circular Collider) is one of the three options considered for the next generation accelerator in high-energy physics as recommended by the European Strategy Group. The layout of FCC-hh has been optimized to a more compact design following recommendations from civil engineering aspects. The updates on the first order and second order optics of the ring will be shown for collisions at the required centre-of-mass energy of 100 TeV. Special emphasis is put on the dispersion suppressors and general beam cleaning sections as well as first considerations of injection and extraction sections., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

In the hadron machine option, proposed in the context of the Future Circular Colliders (FCC) study, the first evaluation of dipole field quality, based on the Nb3Sn technology, has shown a Dynamic Aperture at injection above the LHC target value. In this paper the effect of field imperfections on the dynamic aperture, using the updated lattice design, is presented. Tolerances on the main multipole components are evaluated including feed-down effect., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

High performance collimation systems are required for current and proposed high energy hadron accelerators in order to protect superconducting magnets and experiments. In order to ensure that the collimation system designs are sufficient and will operate as expected, precision simulation tools are required. This paper discusses the current status of existing collimation system tools, and performs a comparison between codes in order to ensure that the simulated interaction physics between a proton and a collimator jaw is accurate., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Transverse feedback systems are used in synchrotrons and storage rings to damp injection oscillations and suppress transverse instabilities. Especially instabilities driven by high intensity beams in future circular colliders such as the FCC set challenging requirements for transverse feedback systems. In order to develop a transverse feedback system able to meet those requirements, sophisticated simulation tools are required. For this purpose, a new modular framework for modeling a transverse feedback system has been developed in Python. The framework can be used as a transverse feedback module in the macro-particle beam dynamics simulation code PyHEADTAIL or as a separate tool for studying a feedback model from a control theory point of view by using a simple signal models for the beam. The main principle of the code is presented and simulation methods used for the conceptual design of the FCC are discussed., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The IFIC High-Gradient (HG) Radio Frequency (RF) laboratory is designed to host a high-power infrastructure for testing HG S-band normal-conducting RF accelerating structures and has been under construction since 2016. The main objective of the facility is to develop HG S-band accelerating structures and to contribute to the study of HG phenomena. A particular focus is RF structures for medical hadron therapy applications. The design of the laboratory has been made through collaboration between the IFIC and the CLIC RF group at CERN. The layout is inspired by the scheme of the Xbox-3 test facility at CERN, and it has been adapted to S-band frequency. In this paper we describe the design and construction status of such a facility., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The transition from a space charge compensated beam in the LEBT to an uncompensated beam in the RFQ will influence the beam parameters. To investigate the impact of the electric fields on the space charge compensation, an insulated cone is used as a repeller electrode in front of the RFQ. Depending on the time dependent potential of the RFQ rods respectively to the beam potential, the compensation electrons may be prevented from moving into the RF field which oozes out of the RFQ entrance. The simulation studies are performed with the particle-in-cell code bender*. The simulations may substantiate measurements at the CW-operated RFQ in Frankfurt University** as well as at the foreseen MYRRHA LEBT-RFQ interface.*** In this contribution, a study on a LEBT-RFQ interface is shown. Results of numerical and experimental investigations will be compared., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Precise proton therapy planning can be assisted by augmenting conventional medical imaging techniques with proton computed tomography (pCT). For adults this requires an incident proton energy up to around 330 MeV, requiring superconducting magnets if an imaging gantry is to replace a conventional 230-250 MeV gantry in the same space. Here we present optics considerations for a superconducting gantry to deliver 330 MeV protons within the context of the future Christie Hospital proton therapy centre, where it is proposed to increase the proton energy in the future with a booster linac., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Crab Cavities will be installed in the High Luminosity LHC in order to increase the effective peak luminosity through a partial compensation of the geometric factor. This will allow extending the levelling time resulting in an increased production of integrated luminosity. Based on the availability of the LHC during 2016 operation, the expected yearly-integrated luminosity of the future HL-LHC was estimated using a Monte Carlo model. Crab cavity faults were added to the observed failure distribu-tions and their impact on integrated luminosity produc-tion as a function of fault time and fault frequency was studied. This allows identifying a breakeven point in luminosity production and defining minimum system availability requirements for the crab cavities to reach the design goal of 250 fb-1 of integrated luminosity per year., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

MedAustron is a synchrotron-based ion beam therapy center allowing the treatment of tumours with protons and other light ion species, in particular C⁶⁺. Commissioning of the first irradiation room for clinical therapy with proton beams has been completed and in parallel to the commissioning of the remaining two irradiation rooms, a facility upgrade study has started. Our analysis includes considerations for the possibility to introduce different extraction mechanisms, new diagnostic tools, optimization of the accelerator cycle time, ripples mitigation for more accurate active beam stabilization and other improvements for hardware reliability. We present the concept, the main benefits, also in terms of treatment time reduction, and the challenges for implementation. Each option will be investigated including a detailed assessment on resources demand, impact and risk analysis., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The recently observed beam induced heating issues in the BGI monitors of the LHC which could have been occurred due to a strong coupling between the beam and the localized modes at the sensor location showed the general importance of a thorough evaluation of the beam coupling impedance and the corresponding heat deposit in beam monitoring equipments. This paper is devoted to the examination of the beam coupling impedance and beam induced heating for a currently under development beam gas ionization (BGI) monitor which is intended to be a part of the CERN Proton Synchrotron (PS) beam monitoring equipment. Details of the EM and wake field simulations for this BGI monitor together with the RF measurement results and power loss calculations will be presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

It is well known that performance of accelerators critically depends on the interaction of high intensity beams with the surrounding structures. As a result of these beam interactions, it is required at CERN to characterize the beam coupling impedance of each new machine element that is to be installed in the accelerator ring. In the framework of the LIU (LHC Injectors Upgrade) project, a new design of rotational wire scanner to be used in the PS Booster is currently under development. As an intermediate step, the prototype of this wire scanner was evaluated with respect to its longitudinal beam coupling impedance. Depending on the performance of this machine element, it is planned to replace existing wire scanners in other machines at CERN (e.g. PS-Booster, PS and SPS) with very similar designs. This paper presents the simulations and describes the measurement methods used for benchmarking electromagnetic simulations performed for the impedance evaluation of the LIU wire scanner for the PS-Booster. Additionally, the device was fitted with an RF feed-through in order to monitor and attenuate certain undesired modes supported by this structure., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Graphene has many excellent properties, such as high electron carrier mobility, good thermal conductivity and transparency etc. The secondary electron yield (SEY) of graphene with copper substrate had been studied in National Synchrotron Radiation Laboratory (NSRL) of China. The results show that the maximum SEY ('max) of 6~8 layers graphene film with copper substrates is about 1.25. Further studies indicate that many factors can affect the SEY test results. The recent SEY tests of graphene films with copper substrates in Daresbury Laboratory (DL) of UK gave the maximum SEY of as-received copper, graphene samples with copper substrates are 1.89, 1.83, and 1.68, respectively, under the incident charge per unit surface (Q) of 7.6×10⁻⁸ C 'mm-2. Meanwhile, the SEY test parameters and measurement results of graphene in both laboratories are compared and analysed. The effect of defects on the SEY results of graphene films with copper substrate is also discussed., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

At ESS, thousands of devices will be used to control both the machine and end-station instruments. To enable ongoing development when access to these devices is not possible (for whatever the reason), Kameleon was implemented. It is a behavior-rich, non-memoryless and time-aware generic simulator that handles clients through a TCP/IP connection. An instance of this client is an EPICS IOC or a Tango Device Server. Kameleon consumes a user-defined file that describes the commands received from a client and, optionally, the reaction to these through statuses sent back to the client. Key features are: 1) Ubiquitous (runs in disparate platforms such as Windows and Linux). 2) Behavior-rich (predefined behaviors as well as user-defined). 3) Non-memoryless (the state of the simulation can be preserved between events and/or elapsed time). 4) Time-aware (statuses can be sent to the client either event-based or time-based). 5) Flexible (commands and statuses are described in a simple user-defined file - nothing is hard-coded in Kameleon). Kameleon will be used in a myriad of scenarios at ESS such as development of EPICS devices support, IOCs, OPI screens, testing of IOCs and alarm workflows., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark