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Study region\ud \ud Combined Sewer Overflows (CSO) of 671 Functional Urban Areas (FUAs) throughout the European Union + UK (EU28), representing almost half of the EU28 population.\ud \ud \ud \ud Study focus\ud \ud CSO loads can be quantified at the local scale through measurements, or with calibrated hydrological models. However, they are difficult to quantify at a large scale (e.g. regional or national), due to a lack of data, and the models used at local scale cannot be applied in the absence of knowledge of the combined sewer (CS) network. This paper presents a 6-parameter lumped hydrological model to simulate a CS network and its overflows, using population and rainfall data of 671 EU28 FUAs.\ud \ud \ud \ud New hydrological insights for the region\ud \ud When properly calibrated, the model can predict the CSO hydrographs as well as aggregated CSO descriptors of a catchment with known impervious surface area connected to a CS with a reasonable reliability. When model calibration is not possible, using default values of the parameters enables a first approximation estimate of CSOs, accurate within one order of magnitude, which can be used to support scenario analysis for regional and continental CSO management. At the EU28 scale, the estimated total CSO volume is 5.7·103 Mm3/y, with a dry weather flow content in CSOs of 460 Mm3/y (assuming a dry weather flow of 200 l/population equivalent (PE)/day including sanitary discharges, industrial discharge and infiltration). A collection of case studies on CSOs is also provided.

The Large Hadron Collider (LHC) is one of the largest scientific instruments ever built. Since opening up anew energy frontier for exploration in 2010, it has gathered a global user community of about 9000 scientists working in fundamental particle physics and the physics of hadronic matter at extreme temperature and density. To sustain and extend its discovery potential, the LHC will need a major upgrade in the 2020s. This will increase its instantaneous luminosity (rate of collisions) by a factor of five beyond the original design valueand the integrated luminosity (totalnumber of collisions) by a factor ten. The LHC is already a highly complexand exquisitely optimised machine so this upgrade must be carefully conceived and will require new infrastructures(underground and on surface)and over a decade to implement. The new configuration, known as High Luminosity LHC (HL-LHC), relies on a number of key innovations that push accelerator technology beyond its present limits. Among these are cutting-edge 11–12Tesla superconducting magnets, compact superconducting cavities for beam rotation with ultra-precise phase control, new technology and physical processes for beam collimation and 100 metre-long high-power superconducting links with negligible energy dissipation, all of which required several years of dedicated R&D; effort on a global international level. The present document describes the technologies and components that will be used to realise the projectand is intended to serve as the basis for the detailed engineering design of the HL-LHC.

Normalmente il contratto di mutuo bancario include clausole dirette a determinare la misura sia del tasso di interessi corrispettivi sia del tasso di interessi moratori. Si esamina perciò il problema se il calcolo in ordine al superamento del tasso soglia usurario debba includere anche la misura degli interessi convenzionali moratori e si sottopongono ad analisi critica i vari argomenti che, specie nella giurisprudenza di legittimità, si portano a sostegno della risposta affermativa, sicché si dimostra la perdurante incertezza degli interpreti sul punto in questione. In alternativa al ricorso alla normativa anti usura, si sostiene l'opportunità di valorizzare altre forme di tutela del mutuatario quale, in particolare, quella rinveniente dall'art. 1384 c.c. che, invero, permette al giudice di ridurre ad equità il tasso degli interessi moratori.

The Large Hadron Collider (LHC) at CERN is built to collide intense proton beams with an unprecedented energy of 7 TeV. The design stored energy per beam of 362 MJ makes the LHC beams highly destructive, so that any beam losses risk to cause quenches of superconducting magnets or damage to accelerator components. Collimators are installed to protect the machine and they define a minimum normalized aperture, below which no other element is allowed. This imposes a limit on the achievable luminosity, since when squeezing β* (the β -function at the collision point) to smaller values for increased luminosity, the β -function in the final focusing system increases. This leads to a smaller normalized aperture that risks to go below the allowed collimation aperture. In the first run of the LHC, this was the main limitation on β* , which was constrained to values above the design specification. In this article, we show through theoretical and experimental studies how tighter collimator openings and a new optics with specific phase-advance constraints allows a β* as small as 40 cm, a factor 2 smaller than β* =80 cm used in 2015 and significantly below the design value β* =55 cm, in spite of a lower beam energy. The proposed configuration with β* =40 cm has been successfully put into operation and has been used throughout 2016 as the LHC baseline. The decrease in β* compared to 2015 has been an essential contribution to reaching and surpassing, in 2016, the LHC design luminosity for the first time, and to accumulating a record-high integrated luminosity of around 40 fb −1 in one year, in spite of using less bunches than in the design.

The main task of the LHC collimation system is to ensure safe and efficient operation, acting as first element of machine protection and minimizing the risk of magnet quenches induced by beam loss. The year 2016 has been very successful in terms of achieved LHC performance, thanks also to the reliability of its collimation system. No magnet quenches due to losses from circulating beam were recorded and an excellent cleaning inefficiency of about 10'4 with 6.5 TeV beams was achieved. The key elements in the set up of an eflicient collimation system, together with the performance obtained with both proton and ion beams, are presented. Main operational improvements with respect to the 2015 run and plans for further upgrades are discussed. Highlights from collimation Machine Development (MD) studies and their implications on collimation performance on the different timescales are also reported.

The commissioning experience of the LHC collimation system in 2016 is reviewed together with the hardware performance. Despite of the limited changes in hardware and software, the time spent in commissioning, set—up and qualification activities has been reduced thanks to system upgrades like the deployment of 100 Hz BLM logging for collimator alignment and detailed commissioning of embedded BPMs. In particular, the reliability and stability shown by embedded BPMs allowed to systematically align TCT collimators and accommodate beam manipulations at the IPs; furthermore, following the gained experience, a proposal of SIS interlock based on the readout of embedded BPMs is made. The LHC collimation system experienced a limited number of faults, which is reported. Hardware changes foreseen for EYETS 2016, mainly dedicated to MD activities. are outlined.

During the long shutdown, a total of 32 collimators were replaced or installed to improve the Run 1 system, including 18 new collimators with embedded beam position monitors , additional physics debris collimators, additional passive absorbers and the re-installation or displacement of existing collimators. The commissioning experience as well as the performance of the collimation system in 2015 is reviewed following these upgrades. In particular, the operational experience with the embedded BPM collimators is discussed, emphasizing the improvements on alignment efficiency and the strategy for better orbit monitoring. Improvements of collimation setting validation through an optimized loss map strategy are also presented. Further improvements planned for 2016 are discussed.

A comprehensive study on the effects of energetic protons on carbon-fiber composites and compounds under consideration for use as low-Z pion production targets in future high-power accelerators and low-impedance collimating elements for intercepting TeV-level protons at the Large Hadron Collider has been undertaken addressing two key areas, namely, thermal shock absorption and resistance to irradiation damage. Carbon-fiber composites of various fiber weaves have been widely used in aerospace industries due to their unique combination of high temperature stability, low density, and high strength. The performance of carbon-carbon composites and compounds under intense proton beams and long-term irradiation have been studied in a series of experiments and compared with the performance of graphite. The 24-GeV proton beam experiments confirmed the inherent ability of a 3D C/C fiber composite to withstand a thermal shock. A series of irradiation damage campaigns explored the response of different C/C structures as a function of the proton fluence and irradiating environment. Radiolytic oxidation resulting from the interaction of oxygen molecules, the result of beam-induced radiolysis encountered during some of the irradiation campaigns, with carbon atoms during irradiation with the presence of a water coolant emerged as a dominant contributor to the observed structural integrity loss at proton fluences ≥5 × 1020 p/cm2. The carbon-fiber composites were shown to exhibit significant anisotropy in their dimensional stability driven by the fiber weave and the microstructural behavior of the fiber and carbon matrix accompanied by the presence of manufacturing porosity and defects. Carbon-fiber-reinforced molybdenum-graphite compounds (MoGRCF) selected for their impedance properties in the Large Hadron Collider beam collimation exhibited significant decrease in postirradiation load-displacement behavior even after low dose levels (∼5 × 1018 p cm-2). In addition, the studied MoGRCF compound grade suffered a high degree of structural degradation while being irradiated in a vacuum after a fluence ∼5 × 1020 p cm-2. Finally, x-ray diffraction studies on irradiated C/C composites and a carbon-fiber-reinforced Mo-graphite compound revealed (a) low graphitization in the "as-received" 3D C/C and high graphitization in the MoGRCF compound, (b) irradiation-induced graphitization of the least crystallized phases in the carbon fibers of the 2D and 3D C/C composites, (c) increased interplanar distances along the c axis of the graphite crystal with increasing fluence, and (d) coalescence of interstitial clusters after irradiation forming new crystalline planes between basal planes and excellent agreement with fast neutron irradiation effects. © 2016, American Physical Society. All rights reserved.

In this paper, we review the functionality and status of the collimation version of SixTrack. It is a simulation tool that contains both an accurate magnetic tracking of an ensemble of particles, as well as a model for particle-matter interaction inside collimators, in order to model the efficiency of a proton collimation system. We summarize recent upgrades and improvements and we review also a benchmark with measured data before finally discussing plans for future development., CERN Yellow Reports: Conference Proceedings, Vol. 2 (2018): Proceedings of "Tracking Collimation" ICFA Workshop

Innovative molybdenum-carbide graphite (Mo-Gr) composites were specifically developed for high energy physics applications. These materials are showing a very promising combination of thermal, electrical, and mechanical properties for application in beam protection elements for high-power accelerators. To date very little is known about their structural and dimensional stability and about degradation of functional properties under irra- diation. Within the EU, FP7, EuCARD-2 project [1], an intense campaign for testing radiation hardness using different particle beams and energies is taking place at GSI Helmholtzzentrum as well as at Brookhaven National Laboratory (USA) and Kurchatov Institute ( Russia).

Chapter 5 in High-Luminosity Large Hadron Collider (HL-LHC) : Preliminary Design Report. The Large Hadron Collider (LHC) is one of the largest scientific instruments ever built. Since opening up a new energy frontier for exploration in 2010, it has gathered a global user community of about 7,000 scientists working in fundamental particle physics and the physics of hadronic matter at extreme temperature and density. To sustain and extend its discovery potential, the LHC will need a major upgrade in the 2020s. This will increase its luminosity (rate of collisions) by a factor of five beyond the original design value and the integrated luminosity (total collisions created) by a factor ten. The LHC is already a highly complex and exquisitely optimised machine so this upgrade must be carefully conceived and will require about ten years to implement. The new configuration, known as High Luminosity LHC (HL-LHC), will rely on a number of key innovations that push accelerator technology beyond its present limits. Among these are cutting-edge 11-12 tesla superconducting magnets, compact superconducting cavities for beam rotation with ultra-precise phase control, new technology and physical processes for beam collimation and 300 metre-long high-power superconducting links with negligible energy dissipation. The present document describes the technologies and components that will be used to realise the project and is intended to serve as the basis for the detailed engineering design of HL-LHC.

Collimators for last-generation particle accelerators like the LHC, must be designed to withstand the close interaction with intense and energetic particle beams, safely operating over an extended range of temperatures in harsh environments, while minimizing the perturbing effects, such as instabilities induced by RF impedance, on the circulating beam. The choice of materials for collimator active components is of paramount importance to meet these requirements, which are to become even more demanding with the increase of machine performances expected in future upgrades, such as the High Luminosity LHC (HL-LHC). Consequently, a farreaching R&D program has been launched to develop novel materials with excellent thermal shock resistance and high thermal and electrical conductivity, replacing or complementing materials used for present collimators. Molybdenum Carbide - Graphite and Copper-Diamond composites have been so far identified as the most promising materials. The manufacturing methods, properties and application potential of these composites will be reviewed along with the experimental program which is to test their viability when exposed to high intensity particle beams.

At the Large Hadron Collider (LHC), dedicated physics debris collimators (TCL) protect the machine from the collision products at the high-luminosity experiments. These collimators reduce the risk of quenches of superconducting magnets by cleaning physics debris losses. One TCL is installed per beam in IR1 and IR5. Several measurements have been performed in 2012 at 4TeV, with peak luminosity values up to 6:3 1033 cm􀀀2 s􀀀1 to address the need of these devices and optimize their settings. They consist in opening the collimator from its nominal setting to an \open" setting, and observing the evolution of the losses measured by the Beam Loss Monitors (BLMs) downstream. All the 2012 measurements are analysed here, including asymmetric measurement with only one jaw. The evolution of the losses as a function of the collimator setting are presented, as well as the loss proles and the ratio of the losses with TCL in over TCL out.

The LHC collimation system has undergone an important upgrade during LS1. A total of 32 collimator installations are taking place to consolidate and improve the Run 1 system. This includes 18 new collimators with embedded beam positions monitors (BPMs), additional physics debris collimators, additional passive absorbers and re-installation or displacement of existing collimators. This paper summarizes the post-LS1 collimation layout, highlighting the expected gains from each modification, and the readiness of the new collimation hardware for commissioning without and with beam. Special emphasis is devoted to the new software for the control and configuration of the BPM colli-mators. A proposal for the necessary beam conditions during collimation alignment and validation with loss maps at 6.5 TeV is also discussed, including a strategy for the machine protection aspects. A list of early machine development studies is proposed.

In 2013, at the end of the LHC physics run I, several quench tests took place with the aim to measure the quench limit of the LHC superconducting magnets. The LHC superconducting magnets in the dispersion suppressor of IR7 are the most exposed to beam losses leaking from the betatron collimation system and represent the main limitation for the halo cleaning. A collimation quench test was performed with 4 TeV proton beams to improve the quench limit estimates, which determine the maximum allowed beam loss rate for a given collimation cleaning. The main goal of the collimation quench test was to try to quench the magnets by increasing losses at the collimators. This note describes the procedure during the test and the first results with the data. Losses of up to 1 MW over a few seconds were generated by blowing up the beam, achieving total losses of about 5.8 MJ. These controlled losses exceeded by a factor 2 the collimation design value, and the magnets did not quench.

In the LHC, high-amplitude particles are cleaned by ei- ther betatron collimators or momentum collimators. Previously, betatron losses have been studied more in detail since considered as a possible performance limitation of the machine. Measurements during the first years of operation show high losses also in the off-momentum cleaning insertion. This causes a significant radiation dose to warm magnets downstream of the collimators. Our work in this paper aims at simulating with SixTrack the off-momentum particles, driven into the momentum collimators by radiation damping outside the RF system acceptance. The re- sults are an important ingredient in assessing the effective- ness of new passive absorbers to protect the warm magnets.

The cleaning inefficiency of the LHC collimation system for the operational scenarios in 2010-12 has already been studied in detail at injection and top energy (450 GeV and 4 TeV respectively). In this paper, results are presented for the cleaning inefficiency at intermediate energies, simulated using the SixTrack code. The first comparisons with measured provoked losses are discussed. This study helps in benchmarking the energy dependence of the simulated inefficiency and is thus important for the extrapolation to future operation at higher energies.

An overview of the collimation system performance during 2012 is described. The collimator " tight " settings for the 60 cm β reach are introduced and the evolution of the cleaning inefficiency achieved throughout the year with one single collimator alignment is presented. The performance of the semi-automatic collimator alignment tools is discussed. We investigate the beam losses through the cycle with emphasis on the yearly evolution of the measured instantaneous beam lifetime in critical phases of the operational cycle. The concept of collimators with integrated beam positions monitors (BPM) is presented here and their effect on the β reach after the long shutdown I is analyzed. The baseline settings strategy for the startup in 2015 is discussed based on the expected performance of the collima-tors with BPMs. New values of β reach are discussed.