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The ECN3 Beam Delivery Task Force was mandated by the PBC Study Group to assess the technical feasibility of increasing the proton beam intensity to the ECN3 hall of the North Area to satisfy the demands of a compelling set of PBC experimental physics proposals. This report summarises the findings of the Task Force that converge on a technically feasible solution with an implementation timeline that could exploit and build upon the investment already foreseen as part of Phase 1 of the NA-CONS project, and take the SPS complex into a new intensity frontier for Fixed Target physics in Run4.

The operation of wire grids and wire scanners as beam profile monitors can be heavily affected, both in terms of measurement accuracy and wire integrity, by the thermal response of the wires to the energy deposited by the charged particles. Accurate measurements of material emissivity are crucial, as Radiative Cooling represent the most relevant cooling process. In this work, we present a method for emissivity measurements of gold-coated tungsten wires based on calorimetric techniques. The dedicated electrical setup allowed allowed transient and steady state measurements for temperatures up to 2000 K. A theoretical description of the measurement technique will be followed up by the electrical set up description and a detailed discussion about the measured results and uncertainties., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

At the CERN Super Proton Synchrotron (SPS) the proton beam is supplied to the fixed target experiments in the North Area facility (NA) via a slow extraction process, taking place at 400 GeV. The monitoring of the spill quality during the extraction, lasting 4.8 seconds with the present SPS setup, is of high interest for minimising beam losses and providing the users with uniform proton-on-target rates. The monitor development challenges include the need for detecting, sampling, processing and publishing the data at rates ranging from few hundred Hz to support the present operation to several hundreds of MHz to serve future experiments proposed within the Physics Beyond Collider (PBC) programme. This paper will give an overview of the ongoing studies for optimizing the existing monitors performances and of the R dedicated to future developments. Different techniques are being explored, from Secondary Emission Monitors to Optical Transition Radiation (OTR), Gas Scintillation and Cherenkov detectors. Expected ultimate limitations from the various methods will be presented, together with 2022 experimental results, for example with a recently refurbished OTR detector., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

The CHARM High-energy Ions for Micro Electronics Reliability Assurance (CHIMERA) working group at CERN is investigating the feasibility of delivering high energy ion beams to the CHARM facility for the study of radiation effects to electronics components engineered to operate in harsh radiation environments, such as space or high-energy accelerators. The Proton Synchrotron has the potential of delivering the required high energy and high-Z (in this case, Pb) ions for radiation tests over the relevant range of Linear Energy Transfer of ~ 10 - 40 MeV cm²/mg with a > 1 mm penetration depth in silicon, specifically for single event effect tests. This contribution summarises the working group’s progress in demonstrating the feasibility of variable energy slow extraction and over a wide range of intensities. The results of a dedicated 6 GeV/u Pb ion beam test are reported to understand the performance limitations of the beam instrumentation systems needed to characterise the beam in CHARM., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

To provide HL-LHC performance, the CERN LHC injector chain underwent a major upgrade during an almost 2-year-long shutdown. In the first half of 2021 the injectors were gradually re-started with the aim to reach at least pre-shutdown parameters for LHC as well as for fixed target beams. The strategy of the commissioning across the complex, a summary of the many challenges and finally the achievements will be presented. Several lessons were learned and have been integrated to define the strategy for the performance ramp-up over the coming years. Remaining limitations and prospects for LHC beam parameters at the exit of the LHC injector chain in the years to come will be discussed. Finally, the emerging need for improved operability of the CERN complex will be addressed, with a description of the first efforts to meet the availability and flexibility requirements of the HL-LHC era while at the same time maximizing fixed target physics output., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

The ability of reliably measuring the transverse beam profile in its injectors is essential for the operation of the LHC. This report aims to assess the reliability, stability, and reproducibility of the new generation of beam wire scanners developed at CERN in the framework of the LHC Injectors Upgrade (LIU). The study includes data from the over 60000 scans performed in 2021 and 2022, with a special focus on reproducibility, investigation of optimal operational settings to ensure a large dynamic range, and evaluation of absolute accuracy through comparison with other instruments present in the injectors., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

In December 2020 the newly commissioned LINAC4 started delivering beam for the CERN proton accelerator chain, replacing the old LINAC2. LINAC4 is a 352 MHz normal conducting linac, providing a beam of negative hydrogen ions at 160 MeV that are converted into protons at injection into the PS Booster synchrotron. In this paper we report on the achieved beam performance, availability, reproducibility and other operational aspects of LINAC4 during its first fully operational year. We also present the machine developments performed and the plans for future improvements., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

In the framework of the LHC Injectors Upgrade project, the Beam Gas Ionisation (BGI) profile monitors installed in the Proton Synchrotron (PS) were fitted with a gas injection system capable of boosting the signal rate high enough to capture single turn acquisitions immediately after injection. This contribution reports on the studies carried out during the beam commissioning of the BGI system in a turn-by-turn matching monitor mode for its eventual implementation in an optimisation framework to preserve emittance during transfer between the PS Booster and PS. The BGI commissioning included a benchmarking with data from a wire-grid secondary emission monitor inserted into the circulating beam., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

The CERN fixed target experimental areas have recently acquired new importance thanks to newly proposed experiments, such as those linked to Physics Beyond Colliders (PBC) activities. Secondary Emission Monitors (SEMs) are the instruments currently used for measuring beam current, position and size in these areas. Guaranteeing their reliability, resistance to radiation and measurement precision is challenging. This paper presents the studies being conducted to understand ageing effects on SEM devices, to calibrate and optimise the SEM design for future use in these beamlines. These include feasibility studies for the application of machine learning techniques, with the objective of expanding the range of tools available for data analysis., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

The LINAC4 is now equipped with two laser profile and emittance meters, basically non destructive and not limited by beam power density. A pulsed laser is transported through fibres and focused into the 160 MeV H⁻ beam. Its interaction with the H⁻ ions detaches electrons that are collected by an electron-multiplier, while the resultingH⁰ particles, after being separated from the main H⁻ beam by a dipole magnet, are recorded by a diamond strip detector, few meters away from the interaction point. The emittance and profile are reconstructed from the laser step by step scan of the beam. After several years of feasibility tests and prototyping, this paper will present all details about the final HW and SW implementation and the 2022 experimental results., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland