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For the high-luminosity upgrade of the Large Hadron Collider, active control of proton/ion beam halo will be essential for safe and reliable operation. Hollow Electron Lenses can provide such active control by enhancing the depletion of halo particles, and are now an integral part of the high luminosity LHC collimation system. The centring of the proton beam within the hollow electron beam will be monitored through imaging the fluorescence from a curtain of supersonic gas. In this contribution we report on the recent progress with this monitor and its subsystems, including the development of an LHC compatible gas-jet injection system, the fluorescence imaging setup and preliminary test measurement in the LHC, Proceedings of the 9th International Beam Instrumentation Conference, IBIC2020, Santos, Brazil

A test stand is under construction at CERN to study high perveance electron guns, electron beam dynamics, and electron beam diagnostics for electron lenses. It will be used to test electron guns for the Hollow Electron Lenses under consideration for beam halo control for High Luminosity LHC (CERN), and for the Space Charge Compensation at SIS18 (GSI) in the frame of the EU funded ARIES project. In order to prepare for this test stand, simulations will be presented and compared with experiments undertaken at the Fermilab (FNAL) electron lens test stand. These were conducted using a hollow electron gun, with the magnetic field configuration and beam current varied to study their effect. The impact of imperfections on the beam dynamics and overall quality of the electron beam will be discussed. A method for comparing experimental data with simulation is also presented to allow bench-marking of the computer models and simulation tools that will later be applied to the analysis of measurements performed at CERN., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

The HIE-ISOLDE Linac (High Intensity and Energy) is a recent upgrade to the ISOLDE facility of CERN, increasing the maximum beam energy and providing means to explore more scientific opportunities. The main software tools required to set up the new superconducting post-accelerator and to characterise the beam provided to the experimental stations will be presented in this paper. Emphasis will be given to the suite of applications to control all beam instrumentation equipment which are more complex compared to the ones in the low energy part of ISOLDE. A variety of devices are used (Faraday cups, collimators, scanning slits, striping foils and silicon detectors). Each serves its own purpose and provides different information concerning the beam characteristics. Every group of devices required a specific approach to be programmed., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

Linac3 is the first link in the chain of accelerators providing highly charged heavy ion beams for the CERN experimental program. The beams, predominantly lead, are produced with the GTS-LHC 14.5 GHz Electron Cyclotron Resonance (ECR) ion source, operated in afterglow mode. In the framework of the LHC Injector Upgrade program (LIU), several activities have been carried out to improve the GTS-LHC and Linac3 performance, in terms of delivered beam current. The extraction region of the GTS-LHC has been upgraded with redesigned apertures and the addition of an einzel lens, yielding improved Linac3 output. Also, a series of measurements has been performed to study the effects of two-frequency heating on the performance of the GTS-LHC. A Traveling Wave Tube Amplifier (TWTA) with variable frequency and pulse pattern was utilized as a secondary microwave source. The two-frequency effect commonly reported with CW operation of ECR ion sources boosting high charge state ion production was also observed in afterglow mode. Lastly, for studies of metal ion beam production, a dedicated test stand has been assembled to characterize the GTS-LHC resistively heated miniature oven performance., Proceedings of the 22nd Int. Workshop on ECR Ion Sources, ECRIS2016, Busan, Korea

The HIE-ISOLDE project* (High Intensity and Energy ISOLDE) reached an important milestone in September 2016 when the first physics run was carried out with radioactive beams at 6 MV/m. This is the first stage in the upgrade of the REX post-accelerator, whereby the energy of the radioactive ion beams was increased from 3 to 5.5 MeV per nucleon. The facility will ultimately be equipped with four high-beta cryomodule that will accelerate the beams up to 10 MeV per nucleon for the heaviest isotopes available at ISOLDE. The first 2 cryomodules of the new linac, hosting each five superconducting cavities and one solenoid, were commissioned in August 2016. Besides demonstrating the experimental capabilities of the facility, this successful first run validated the technical choices of the HIE ISOLDE team and provided a fitting reward for eight years of rigorous R&D efforts. At the start of 2018, HIE-ISOLDE is expected to complete the energy upgrade, reaching 10 MeV/u and becoming an attractive facility for a wide variety of experiments. This contribution will focus on the results of the commissioning and on the main technical issues that were highlighted., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The High Intensity and Energy (HIE) upgrade to the on-line isotope separation facility (ISOLDE) facility at CERN is currently in the process of being commissioned. The very tight space available between the superconducting acceleration cavities and a challenging specification led to the design of a compact 'diagnostic box' with a number of insertable instruments on a common vacuum chamber. The box was conceived in partnership with the engineering firm AVS and produced as a completed assembly in industry. 14 diagnostic boxes have been installed and are now operational. This paper will describe the design, the construction and first results from operation of these HIE ISOLDE diagnostic boxes., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain

The High Intensity and Energy ISOLDE project (HIE-ISOLDE)* is a major upgrade of the ISOLDE facility at CERN. The energy range of the post-accelerator will be extended from 2.85 MeV/u to 9.3 MeV/u for beams with A/q = 4.5 (and to 14.3 MeV/u for A/q = 2.5) once all the cryomodules of the superconducting accelerator are in place. The project has been divided into different phases, the first of which (phase 1a) finished in October 2015 after the hardware and beam commissioning were completed**. The physics campaign followed with the delivery of both radioactive and stable beams to two different experimental stations. The characteristics of the beams (energies, intensities, time structure and beam contaminants) and the plans for the next experimental campaign will be discussed in this paper., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

Phase 1a of the High Intensity and Energy ISOLDE (HIE-ISOLDE) project* was completed in 2015. The first cryomodule and two High Energy Beam Transfer lines (HEBT) were installed. In addition, many of the subsystems of the normal conducting part of the post-accelerator (REX) were renovated or refurbished. Following the hardware commissioning of the different system** and, in preparation for the start of the physics program, many tests and measurements were conducted as part of the beam commissioning program. The results of these tests and the plan for the next beam commissioning campaign are discussed in this paper., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The HIE ISOLDE project [1] reached a major milestone in October 2015, with the start of the first physics run with radioactive ion beams. This achievement was the culminating point of intense months during which the first cryomodule of the HIE ISOLDE superconducting Linac and its high-energy beam transfer lines were first installed and subsequently brought into operation. Hardware commissioning campaigns were conducted in order to define the envelope of parameters within which the machine could be operated, to test and validate software and controls, and to investigate the limitations preventing the systems to reach their design performance. Methods and main results of the first commissioning of HIE ISOLDE post accelerator, including the performance of the superconducting cavities with beam, will be reviewed in this contribution., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The HIE-ISOLDE project (High Intensity and Energy ISOLDE) reached an important milestone in October 2015 when the first physics run was carried out with radioactive Zn beams at 4 MV/m. This is a first stage in the upgrade of the REX post-accelerator, whereby the energy of the radioactive ion beams was increased from 3 to 4.3 MeV per nucleon. The facility will ultimately be equipped with four high-beta cryomodules that will accelerate the beams up to 10 MeV per nucleon for the heaviest isotopes available at ISOLDE. The first cryomodule of the new linac, hosting five superconducting cavities and one solenoid, was commissioned in summer 2015, while the second one was being assembled in clean room. The new high-energy beam transfer lines were installed and commissioned in the same lapse of time. Commissioning with two cryomodules is planned for Summer 2016 to prepare for a physics run at 5.5 MeV/u in the second half of the year. This contribution will focus on the results of the commissioning and operation of the SC linac in 2015. Plans for the second phase of the HIE-ISOLDE project will be highlighted., Proceedings of the 28th Linear Accelerator Conf., LINAC2016, East Lansing, MI, USA