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This conceptual design report provides a detailed account of the European Spallation Source neutrino Super Beam (ESS$\nu$SB) feasibility study. This facility has been proposed after the measurements reported in 2012 of a relatively large value of the neutrino mixing angle $\theta_{13}$, which raised the possibility of observing potential CP violation in the leptonic sector with conventional neutrino beams. The measured value of $\theta_{13}$ also privileges the $2^{nd}$ oscillation maximum for the discovery of CP violation instead of the more typically studied $1^{st}$ maximum. The sensitivity at this $2^{nd}$ oscillation maximum is about three times higher than at the $1^{st}$ one, which implies a reduced influence of systematic errors. Working at the $2^{nd}$ oscillation maximum requires a very intense neutrino beam with an appropriate energy. The world's most intense pulsed spallation neutron source, the European Spallation Source (ESS), will have a proton linac operating at 5\,MW power, 2\,GeV kinetic energy and 14~Hz repetition rate (3~ms pulse duration, 4\% duty cycle) for neutron production. In this design study it is proposed to double the repetition rate and compress the beam pulses to the level of microseconds in order to provide an additional 5~MW proton beam for neutrino production. The physics performance has been evaluated for such a neutrino super beam, in conjunction with a megaton-scale underground water Cherenkov neutrino detector installed at a distance of 360--550\,km from ESS. The ESS proton linac upgrades, the accumulator ring required for proton-pulse compression, the target station design and optimisation, the near and far detector complexes, and the physics potential of the facility are all described in this report. The ESS linac will be operational by 2025, at which point the implementation of upgrades for the neutrino facility could begin., Comment: 216 pages

The goal of the ESS𝜈SB project is to discover and measure neutrino CP violation with unprecedented sensitivity. The associated ESS𝜈SB H2020 Design Study is aimed at investigating and proposing a conceptual design of a new neutrino superbeam in Europe. The Target Station is a key element of this project, since it will produce a high intensity neutrino superbeam from a 5MW proton beam delivered by the European Spallation Source at Lund. Work Package 4 of this project focuses on the optimization of the physics performance of the elements producing the beam, such as the targets and the magnetic horns, as well as on the technical aspects related to the Target Station design. The 5MW proton beam will be split laterally into four 1.25MW beams, each with 1.3 μs proton pulses and 14 Hz repetition rate, which will hit four separate targets inserted inside four horns. The production of the neutrino beam under such conditions requires the development of technologies capable of working at a MW power scale, both for the target and for the other components of the target station facility.

Parallel Flash Talk at the "XIX International Workshop on Neutrino Telescopes" on line - 18-26 February, 2021, Funded by the Horizon 2020 Framework Programme of the European Union

International audience; The PRECy project foresees the use of a 16–25 MeV energy proton beam produced by the TR24 cyclotron, named CYRCé, recently installed at the Institut Pluridisciplinaire Hubert Curien (IPHC) in Strasbourg for research in radiation biology. One of the exit ports of the cyclotron will be used for this application along with a combination magnet. The platform will consist of up to 5 experimental stations linked to beamlines located in a dedicated area next to the cyclotron vault. One of the beamlines will receive proton beams of a few cm diameter at intensities up to 100 nA. In order to characterize the beam extracted from the cyclotron, the transverse beam emittance was studied by means of different methods.

The first two extension beamlines from the CYRCé cyclotron have been developed and recently commissioned at IPHC Strasbourg. One beamline is devoted to radiobiological experiments, the PRECy project, while the other one is for testing silicon detector modules in the framework of the CMS experiment. The development of the control system of these beamlines is reported in this paper.

A new target and ion source unit has been developed at CERN-ISOLDE with the aim of delivering isobarically clean beams of short lived neutron-rich Cd and Zn. A quartz insert in the transfer line allows the retention and the decay of alkali contaminants by controlling its temperature from 308 °C to 792 °C. This paper presents the design of this transfer line. New alkali suppression factors are deduced from 80Rb, 8Li, 46K and 126,142Cs yield measurements. The enthalpy of adsorption for Rb and Cs is calculated from 80Rb and 126Cs suppression factors. The yield of 77Ga and 96Sr are presented.

The heart of every ISOL (isotope separation on-line) facility is its target and ion source system. Its efficiency, selectivity and rapidity is decisive for the production of intense and pure ion beams of short-lived isotopes. Recent progress in ISOL target and ion source technology is discussed at the examples of radioactive ion beams of exotic zinc and tin isotopes that were purified by isothermal chromatography and molecular sideband separation respectively. An outlook is given to which other elements these purification methods are applicable.

A new target and ion source unit has been developed at CERN-ISOLDE with the aim of delivering isobarically clean beams of short lived neutron-rich Cd and Zn. A quartz insert in the transfer line allows the trapping and the decay of alkali contaminants. This paper presents the design of the quartz transfer line. Alkali suppression is demonstrated with 80Rb and 114Cs. The yield of 8Li, 46K, 77Ga and 75Zn is presented.

Copper oxide films have been sputter deposited on glass substrates by reactive radio frequency (rf) magnetron sputtering, using a solid copper target and an argon–oxygen gas atmosphere. The films were characterised by scanning electron microscopy/energy dispersive analysis of X-rays, X-ray photoelectron spectroscopy, atomic force microscopy, profilometry, spectrophotometry and surface energy measurements. The effect of input rf power and oxygen flow rate during deposition on the dispersive, polar and acid–base components of the surface energy of the copper oxide films was investigated. The components of the surface energy were determined by the Owens–Wendt and the Van Oss–Chaudhry–Good method. The Lifshitz–van der Waals dispersive interaction force was found to be the major contributor to the surface energy of the films and the origin of their hydrophobicity. Optical transmission in the prepared films was measured by spectrophotometry in the 400–850 nm wavelength region. We observed a maximum transmission of between 40% and 80% for copper oxide films prepared at a low rf power of 200 W, for the oxygen flow rates investigated. The optical bandgap values of the films ranged between 2.4 and 2.05 eV. The dependence of the optical properties of the films like optical transmittance and optical bandgap on deposition parameters like input rf power and physical properties like thickness and roughness was investigated in the wavelength range 400–850 nm. This information is expected to underlie the successful development of durable copper oxide films for technological applications requiring controlled optical transmission in the visible.

Copper oxide films were sputter deposited on glass substrates by reactive rf magnetron sputtering, using a solid copper target and an argon-oxygen gas atmosphere. The films were characterized by scanning electron microscopy, atomic force microscopy, and spectrophotometry. The effect of input power and oxygen flow rate on the dispersive, polar, and acid-base (AB) components of the surface energy of the films was evaluated. The extended Derjaguin-Landau-Verwey-Overbeek (DLVO) theory was used to analyze the factors controlling the interaction of copper oxide films with their environment. The components of the surface energy were determined by the Owens-Wendt and the Van Oss-Chaudhury-Good approaches, using water, ethylene glycol, and diiodomethane as the probe liquids. The Lifshitz-Van der Waals (LW) dispersive interaction force was found to be the major contributor to the surface energy of the films. In addition, we observed that other phases of copper oxide such Cu2O and mixed Cu2O/CuO are also hydrophobic. Black optically absorbing CuO has been previously identified as a hydrophobic phase. Transparent Cu2O films hold substantial promise as antistiction coatings in micromirror arrays for micro-electromechanical systems applications. Copper oxide films also have potential aerospace applications as low friction coatings.

Copper oxide films have been sputter deposited on glass substrates by reactive rf magnetron sputtering, using a solid copper target and an argon–oxygen gas atmosphere. The films were characterized by SEM/EDAX, XPS, AFM, profilometry and spectrophotometry. Optical transmission in the prepared films was measured by spectrophotometry in the 400–850 nm wavelength region. The optical transmission was found to increase from below 10% to above 80% as the rf power was reduced from 800 to 200 W at a wavelength of 550 nm. The optical bandgap value also increased from 2.05 to 2.4 eV with a reduction in rf power from 800 to 200 W. This bandgap change indicates the possibility of selectively depositing an optically transparent Cu2O-rich film, an absorbing black CuO-rich film or a mixture of both phases by varying the rf power during deposition. The oxygen flow rate during deposition had a less significant effect on the optical transmittance and bandgap of the films. This dependence of the stoichiometry of the copper oxide films on the deposition conditions is explained in terms of the sticking coefficient, nucleation rates and migration of impinging copper and oxygen species on the substrate. This information is expected to underlie the successful development of copper oxide films for technological applications requiring controlled optical transmission in the visible.

The Beta-Beam is a concept of large-scale facility that aims at providing pure electronic neutrino and antineutrino beams for the measurement of $ \nu_{e}^{}$ $ \rightarrow$ $ \nu_{\mu}^{}$ oscillations. Beta-decaying nuclides are produced in large amounts in a facility of the scale of EURISOL, and are then post-accelerated and stored at large $ \gamma$ in a racetrack decay ring. We present here a conceptual design of the accelerator chain of a Beta-Beam based at CERN.

Oxide targets used nowadays in ISOL facilities can only accommodate up to a few kW incoming beam power because of the targets’ moderate operation temperatures and their low thermal conductivities. A generic design to accommodate a 100 kW, 1 GeV proton beam, used as baseline parameters in the ongoing EURISOL‐DS project, along with the numerical and experimental tools required for its validation, are reported here. We provide some details on these high‐power composite oxide‐refractory metal targets and on the proposed arrangement in several sub‐units merging into a single ion source.

The barrel part of the CMS electromagnetic calorimeter consists of about 75 000 Lead Tungstate (PbWO 4 ) crystals arranged in 36×4 modules which are assembled in two Regional Centres, in Rome and at CERN. Two automatic machines have been designed to check the crystal quality before assembly. The main crystal characteristics are compared to a set of specifications included in the contract with the crystal producers. The measurement stability and cross-calibration between the two machines is a fundamental issue, which has to be monitored throughout the construction phase. This paper describes comparisons between measurements made at the two regional centres to ensure a consistent and reliable crystal quality control.

Report on the prototype target irradiation done at PSI - TARPIPE

Tools and developments required to go from today\'s operating standards to the 100kW benchmark targets.

Design and online tests at CERN-ISOLDE of a \\\"bivalve\\\" target unit with two CaO containers with merging lines an remotely actuated valves into a single MK7 cold FEBIAD ion source. Details on the development of the unit and online results are provided.

Project proposal to test an oxide target at high power at TRIUMF

Final report on the high power oxide prototype tests done at TRIUMF

The ISOLDE facility at CERN has constantly developed new ion beams with betterpurity and improved yields over the last decades. Chemical selectivity for the productionof pure RIBs can be achieved by condensation of less volatile species in the transferline between the target and the ion source and by selective ionisation schemes such asthat provided by Resonance Ionization Laser Ion Source (RILIS)...

Parallel Flash Talk at the "XIX International Workshop on Neutrino Telescopes" on line - 18-26 February, 2021