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The beam stored energy and the peak intensity of CERN Large Hadron Collider (LHC) will grow in the next few years. The former will increase from the 320 MJ values of Run2 (2015-2018) to almost 540 MJ during Run3 (2022 onwards) and 680 MJ during the HL-LHC era putting stringent requirements on beam intercepting devices, such as absorbers and dumps. The HiRadMat-56-HED (High-Energy Dumps) experiment performed in Autumn 2021 executed at CERN HiRadMat facility employed the Super Proton Synchrotron accelerator (SPS) 440 GeV/c proton beam to impact different low-density carbon-based materials targets to assess their performance to these higher energy beam conditions. The study focused on advanced grades of graphitic materials, including isostatic graphite, carbon-fiber reinforced carbon and carbon-SiC materials in addition to flexible expanded graphite. Some of them specifically tailored in collaboration with industry to very specific properties. The objectives of this experiment are: (i) to assess the performance of existing and potentially suitable advanced materials for the currently operating LHC beam dumps and (ii) to study alternative materials for the HL-LHC main dump or for the Future Circular Collider dump systems. The contribution will detail the R phase during design, the execution of the experiment, the pre-irradiation tests as well as the first post irradiation examination of the target materials. Lessons learnt and impact on operational devices will also be drawn., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

During CERN’s LS2, several upgrades were performed to beam intercepting devices in the framework of the HL-LHC Project. Upgraded equipment includes two internal beam dumps (TDIS) intended for machine protection located at the injection points from the SPS to the LHC. These two devices have been assembled, tested, and installed around LHC Point 2 and Point 8 and are currently ready to get commissioned with the beam. They are 5.8m-long, three-module-segmented vacuum chambers, with large aperture to accommodate the injected and circulating beam and equipped with absorbing materials, These comprise graphite and higher Z alloys that are embedded on sub-assemblies reinforced with back-stiffeners made of TZM. The current contribution covers three main matters. First, it details the TDIS design and its key technical features. The second topic discussed is the outcome of an experiment where a prototype module was tested under high-energy beam impacts at CERN’s HiRadMat facility. To conclude it is presented the return of experience from the pre-series construction, validation and installation in the LHC tunnel., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

The use of a bent crystal was investigated in order to reduce the losses at the CERN Super Proton Synchrotron (SPS) electrostatic septa (ZS) during the slow extraction of 400 GeV protons toward the North Area. The crystal, installed a few meters upstream the ZS, bends protons that would otherwise impinge on the ZS wires. Since particle deflection with good efficiency is achieved only when the crystal lattice is aligned within ~10 urad to the trajectory of the particles (at p = 400 GeV/c), a compact goniometer was built to allow the correct angular alignment of the crystal with respect to the incoming beam with a precision of few urad. In this paper, we report on the crystal features measured during a dedicated beam test by the UA9 experimental installation in the CERN H8 beam line. Details of the goniometer and its installation are also reported. The first results achieved during dedicated Machine Development (MD) sessions are finally presented., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

Slow extraction using the third-integer resonance and thin electrostatic septa as used in the SPS to serve the North Area is a process with inherent beam loss. For high-flux 400 GeV protons, the beam losses result in high machine activation, reduced component lifetime and severe limitations on personnel access and maintenance. The instantaneous and integrated loss levels are strong limitations on the annual attainable POT for present operation and for the much higher fluxes requested by SHiP at the proposed BDF facility. In this report the present constraints and potential improvements to the slow extraction system in the SPS are described along with the recent theoretical studies and practical implementation of prospective operational improvements. Machine results of testing of new extraction loss reduction techniques and hardware are presented in the context of SHiP POT requests, SPS BDF and the PBC project and the potential extraction loss reduction factor is evaluated with an outlook to future high intensity operation. The prospects of deployment on the present operational beams and the resulting improvement factors are discussed.

Antiprotons are produced at CERN by impacting intense proton beams of 26 GeV/c onto a high-Z water-cooled target. The current design consists in an Ir core target in a graphite matrix and inserted in a Ti-6Al-4V assembly. A new target design has been foreseen for operation after 2021 aiming at improving the operation robustness and antiproton production yield, triggering several R&D activities during the last years. First, both numerical (use of hydrocodes) and experimental approaches were carried out to study the core material response under extreme dynamic loading when impacted by the primary proton beam. The lessons learnt from these studies have been then applied to further prototyping and testing under proton beam impact at the CERN-HiRadMat facility. A first scaled prototype consisting in Ta rods embedded in an expanded graphite matrix was irradiated in 2017, while in 2018, the PROTAD experiment will test different real-scale AD-Target prototypes, in which the old water-cooled assembly is replaced by a more compact air-cooled one, and different core geometry and material configurations are investigated. This contribution details these prototyping and testing activities., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada