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The Future Circular Collider (FCC) is one possible future successor of the Large Hadron Collider (LHC). The proton-proton collider center-of-mass collision energy is set to 100 TeV with a beam current of 0.5 A. To reach this goal a stable acceleration is critical and therefore higher order modes (HOM) need to be damped. To avoid a high power level in the HOM dampers, further described as couplers, the loaded Q-factor should be below 1000 for the cavity with mounted HOM couplers. Besides a low Q-factor the R/Q value should also be in the range of 1 Ω or below. Two different types of couplers are used to achieve a high damping. The two types are a narrowband Hook-type HOM coupler and a broadband Probe-type HOM coupler. The recent results of the design of the HOM couplers attached to a superconducting 400 MHz RF cavity will be presented., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

An S-band (2856 MHz) spherical cavity pulse compressor has been designed, fabricated and tested in the Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS). The pulse compressor consists of a special 3 dB coupler and only one spherical energy storage cavity, two TE114 modes are chosen to oscillate in which for fairly high unload Q factor. The prototype was made of aluminum for studying the performance of the pulse compressor and checking the validity of the simulations. The cold test results of the aluminum cavity are also presented. The copper coating on the whole internal surface of the aluminum spherical cavity is in progress and the test results will also be presented in the future., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Auto-tuning magnet girder is one of the key technolo-gies to be solved for HEPS-TF (Test Facility of High Ener-gy Photon Source). The girder should have high adjusting accuracy, high stability and can be beam-based aligned, to obtain the stability requirements of beam orbit. There are two girders developed, and the tests have been done. The accuracy of girder motion is within 10 microns while the adjusting range is 1 mm and the resolution is better than 1 microns, the natural frequency is higher than 24 Hz., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

FELiChEM is a new experimental facility under construction at the University of Science and Technology of China. There are more than one hundred important devices to construct it, which core device is two free electron laser oscillators generating middle-infrared and far-infrared laser and covering the spectral range of 25-200μm. The optical cavity is an important component of oscillator which very sensitive to misalignment errors of the mirror, due to its near-concentric and symmetric structure. High precision alignment and installation is necessary to ensure the smooth implementation of the FELiChEM project. Laser tracker and Level are used to install this devices according to the alignment control network. An efficient and high-precision alignment method based on autocollimator and photoelectric auto-collimator is used to align optical cavity of oscillator. This methods is proven to be effective and meet the tolerances by multiple means., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Charge strippers are almost inevitable for accelerations in heavy-ion accelerator complex. The fixed solid strip-pers including carbon-foil strippers are difficult to be used in on-going or upcoming new-generation in-flight RI beam facilities, e.g., RIBF (RIKEN, Japan), FAIR (GSI, Germany), FRIB (NSCL/MSU, US), HIAF (IMP, China) and RAON (RISP, Korea). The He gas stripper developed at RIBF is the first successful stripper significantly be-yond the applicable limit of the fixed carbon-foil strip-pers. We discuss the development of the gas strippers at RIBF and overview the related new-generation strippers being developed in the world., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

This contribution shows the progress in the development of a plasma window at the institute for applied physics at Goethe University Frankfurt. A plasma window* is a membrane free transition between two regions of different pressure, enabling beam transmission from a rough vacuum area (~1 mbar) to a higher pressure (up to 1 bar) region on short length scales. In comparison to differential pumping stages a length reduction by a factor of up to 100 is achievable, while the absence of a solid membrane yields prolonged operation time. The sealing effect is based on the high temperature arc discharge sustained in a cooled copper channel between the pressure regimes. Due to a bulk temperature around 10,000K** the viscosity of the gas is dramatically increased, leading to a slower gas flow, enabling a higher pressure gradient. This contribution will present first results regarding the pressure gradient in dependence of the discharge current and the aperture. Until now, a pressure factor around 100 has been established for well over 50 min. This contribution goes along with the one from Mr. A. Michel, he focuses on the spectroscopic analysis of the arc plasma., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Pure, intense rare isotope beams at a wide range of energies are crucial to the nuclear science programs at TRIUMF. The CANREB project will deliver a high resolution spectrometer (HRS) for beam purification, and a charge breeding system consisting of a radiofrequency quadrupole (RFQ) beam cooler and buncher, an electron beam ion source (EBIS), and a Nier-type spectrometer to prepare the beam for post-acceleration. Bunching the beam prior to charge breeding will significantly enhance the efficiency of the EBIS. The RFQ buncher will accept continuous §I{60}{keV} rare isotope beams from the ARIEL or ISAC production targets and efficiently deliver low emittance bunched beams. A pulsed drift tube (PDT) will adjust the energy of the bunched beam for injection into the EBIS to match the acceptance of the post-accelerating RFQ. Ion optical simulations were carried out to inform the design of the RFQ buncher and PDT. Simulations indicate that delivery of up to 10⁷~ions per bunch with high efficiency is possible. Experience with previous beam bunchers was also brought to bear in the design effort. Installation of the RFQ is under way, and tests with offline beam are expected to be performed in late 2018., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

The Facility for Rare Isotope Beams (FRIB) is developing a 5-cell 644 MHz β_{o}pt=0.65 elliptical cavity for a future linac energy upgrade to 400 MeV/u for the heaviest uranium ions. Superconducting elliptical cavities operated in continuous wave, such as the ones for FRIB, are prone to microphonics which can excite mechanical modes of the cavities. It has been shown that the detuning due to microphonics can be mitigated with the use of piezo actuators (fast tuner) as opposed to the costly option of increasing the input RF power. The FRIB slow/fast dynamic tuner will be based on the Fermilab experience with similar tuners like those developed for the linac coherent light source (LCLS) II and proton improvement plan (PIP) II. This paper will present the results of tuner properties on the bench., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

CERN's specialized structures such as particle detectors are built to have high rigidity and low weight, which comes at a cost of their high fragility. Shock and vibration issues are a key element for their successful transport, handling operations around the CERN infra-structure, as well as for their operation underground. The experimental modal analysis measurement technique is performed to validate the Finite Element Analysis in the case of complex structures (with cables and substructure coupling). In the case of lightweight structures, standard contact measurements based on accelerometers are not possible due to the high mass ratio between the accelerometers and the structure itself. In such a case, the vibration of the structure can be calculated based on the Doppler shift of the laser beam reflected off the vibrating surface. This paper details the functioning and application of an advanced laser-scanning vibrometry system, which utilizes the fore-mentioned non-contact method. The results of the Experimental Modal Analysis of selected lightweight structure using this instrument is also presented and discussed., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

An S-Band High-Gradient (HG) Radio Frequency (RF) laboratory is under construction and commissioning at IFIC. The purpose of the laboratory is to perform investigations of high-gradient phenomena and to develop normal-conducting RF technology, with special focus on RF systems for hadron-therapy. The layout of the facility is derived from the scheme of the Xbox-3 test facility at CERN* and uses medium peak-power (7.5 MW) and high repetition rate (400 Hz) klystrons, whose RF output is combined to drive two testing slots to the required power. The design and construction of the various components of the system started in 2016 and has been completed. The installation and commissioning of the laboratory is progressing, with first results expected before mid 2018. The technical characteristics of the different elements of the system and the commissioning status together with preliminary results are described.

We present the design for a simple, variable-focus solenoidal lens with integrated emittance filtering. The design was developed as a first-iteration injection optics solution for transport of a beam from a field-emitter cathode into a dielectric laser accelerator structure. The design is easy to fabricate and, while based on permanent magnets, can readily be modified to allow for remote control of the focal length. The emittance is controlled via selection of collimating irises. The focal length can be changed by altering the spacing between two permanent ring magnets. Results from fabrication and initial testing will be presented., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Siemens communication module CP1616 is a high-performance PROFINET controller, which can support both Real-time (RT) and Isochronous Real-Time (IRT) communication. Experimental Physics and Industrial Control System (EPICS) is a wildly used distributed control system in large scientific devices. In order to integrate PROFINET protocol into EPICS environment, we developed this driver based on CP1616 and established the prototype system. This paper will describe the design of EPICS driver for CP1616 and the test result of the prototype system., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Beam windows are usually used to isolate vacuum or other special environments, which is a key device for high-power accelerators. Graphene has extremely high thermal conductivity, high strength and high transparency to high energy ions. It is highly suitable for beam windows if the technology is allowable. This paper will discuss the primary tests of graphene films, including vacuum per-formance and thermal conductivity performance, as well as the simulated performance of an assumed graphene window., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

This paper assesses the continued suitability of an existing Water Cooling System (WCS) for cooling intermediate and high-power RF power amplifiers at the Los Alamos Neutron Science Center (LANSCE). At LANSCE, the high-power and intermediate power amplifiers installed in the 70s were at end-of-life with obsolete parts and no suitable replacements available to extend their life. The LANSCE Refurbishment Project was initiated (now complete) to replace these amplifiers and to utilize already existing WCSs. Two existing WCSs were repurposed and one new WCS was designed and installed. Unscheduled, intermittent water system trips on one of the WCSs has prompted the engineering group to drill down into the original decision, build a flow model and assess some of the legacy components' suitability to solve the problem. This paper discusses the general approach, troubleshooting and solution recommendations to be made for resolution of the intermittent issues., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Beam window is a key device in high-intensity hadron beam applications, and it is usually used to separate air or other gas environments in the end of beam vacuum duct. Compared with the usually-used window materials such as Inconel alloy, Aluminum alloy and so on, the graphene has extremely high thermal conductivity, high strength and high transparency to high-energy ions. With the maturation of large-size graphene manufacturing technology, we have studied this new-type window for MW-class proton beam. The thermal analyses by the theoretical formula and simulations based on FEA are presented in this paper. Simultaneously, the scattering effect and the lifetime are also discussed. The preliminary results are promising. The same material can also be possibly applied to other devices such as charge-exchange stripping foils, beam monitors and so on., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

An S-Band High-Gradient (HG) Radio Frequency (RF) laboratory is under construction and commissioning at IFIC. The purpose of the laboratory is to perform investigations of high-gradient phenomena and to develop normal-conducting RF technology, with special focus on RF systems for hadron-therapy. The layout of the facility is derived from the scheme of the Xbox-3 test facility at CERN* and uses medium peak-power (7.5 MW) and high repetition rate (400 Hz) klystrons, whose RF output is combined to drive two testing slots to the required power. The design and construction of the various components of the system started in 2016 and has been completed. The installation and commissioning of the laboratory is progressing, with first results expected before mid 2018. The technical characteristics of the different elements of the system and the commissioning status together with preliminary results are described., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada