39 research outputs found

    Equipment for tunnel installation of main and insertion LHC cryo-magnet

    Get PDF
    The installation of about 1700 superconducting dipoles and quadrupoles in the Large Hadron Collider (LHC) is now well underway. The transport and installation of the LHC cryo-magnets in the LEP tunnels originally designed for smaller, lighter LEP magnets have required development of completely new handling solutions. The severe space constraints combined with the long, heavy loads have meant that solutions had to be very sophisticated. The paper describes the procedure of the installation of the main cryo-magnets in the arc as well as the more specific insertion cryo-magnets. The logistics for the handling and transport are monitored with tri-axial acceleration monitoring devices that are installed on each cryo-magnet to ensure their mechanical and geometric integrity. These dynamic results are commented. The paper includes conclusions and some lessons learne

    Design development and implementation of an irradiation station at the neutron time-of-flight facility at CERN

    Get PDF
    A new parasitic, mixed-field, neutron-dominated irradiation station has been recently commissioned at the European Laboratory for Particle Physics (CERN). The station is installed within the neutron time-of-flight (n_TOF) facility, taking advantage of the secondary radiation produced by the neutron spallation target, with neutrons ranging from 0.025 eV to several hundreds of MeV. The new station allows radiation damage studies to be performed in irradiation conditions that are closer to the ones encountered during the operation of particle accelerators; the irradiation tests carried out in the station will be complementary to the standard tests on materials, usually performed with gamma sources. Samples will be exposed to neutron-dominated doses in the MGy range per year, with minimal impact on the n_TOF facility operation. The station has 24 irradiation positions, each hosting up to 100 cm3 of sample material. In view of its proximity to the n_TOF target, inside protective shielding, the irradiation station and its operating procedures have been carefully developed taking into account the safety of personnel and to avoid any unwanted impact on the operation of the n_TOF facility and experiments. Due to the residual radioactivity of the whole area around the n_TOF target and of the irradiated samples, access to the irradiation station is forbidden to human operators even when the n_TOF facility is not in operation. Robots are used for the remote installation and retrieval of the samples, and other optimizations of the handling procedures were developed in compliance with radiation protection regulations and the aim of minimizing doses to personnel. The sample containers were designed to be radiation tolerant, compatible with remote handling, and subject to detailed risk analysis and testing during their development. The whole life cycle of the irradiated materials, including their post-irradiation examinations and final disposal, was considered and optimized

    Robotics remote handling of a collimator

    No full text
    Open days activité robotique l'installation d'un collimateur en remot

    How to Manage a Large Scale Beam Line Consolidation in a Highly Activated Area?

    No full text
    The TDC2/TCC2 consolidation is a good example showing how the complexity of interventions in high radiation areas has increased over the last five years. Due to its duration, its dispersion, the diversity of the teams involved, the fixed deadlines, the risks and external constraints, this worksite prefigures large scale-interventions in the LHC during long shutdown 2 (LS2) and even more LS3. The paper describes the three main project phases: preparation, execution (including monitoring and control) and closure emphasizing the indispensable steps in each stage. It also explains why integrating scope, schedule and dose into a single baseline is of prime importance and shows how to manage and monitor the radiation safety performance of the various interventions throughout the execution phase. Eventually, some recommendations are formulated in order to better accommodate the design of high radiation areas to their operation and maintenance constraints

    Les entreprises de biens de consommation sous l’Occupation

    No full text
    Ce volume prolonge l'histoire de la vie économique et des entreprises sous l'Occupation avec l'étude d'une nouvelle branche, les industries de consommation, entendues largement, de l'agro-alimentaire à l'automobile, en passant par le textile. Il s'inscrit également dans une historiographie des entreprises de biens de consommation en plein renouvellement depuis une décennie, qui s'intéresse autant à l'histoire industrielle et commerciale qu'à celle des attitudes des consommateurs. Le cadre retenu privilégie le point de vue de l'entreprise en étudiant à la fois les conditions de fabrication des biens de consommation et l'organisation des circuits de vente ; il ne néglige pas pour autant l'approche par les consommateurs. La vie des entreprises est marquée par des conditions d'approvisionnement difficiles, qui les obligent à recourir à des produits de remplacement. Comment parviennent-elles à échapper aux prélèvements de main d'œuvre et aux mesures de concentration ? Doivent-elles transformer leur production pour répondre aux exigences de l'occupant en particulier Dans quelle mesure réalisent-elles cependant des profits importants ? Autant de questions auxquelles cet ouvrage, qui s'appuie sur les recherches récentes des meilleurs spécialistes français et étrangers, s'efforce de répondre

    A Beam Dump Facility (BDF) at CERN – The Concept and a First Radiological Assessment

    No full text
    The Beam Dump Facility (BDF) Project, currently in its design phase, is a proposed general-purpose fixed target facility at CERN, dedicated to the Search for Hidden Particles (SHiP) experiment in its initial phase and whose aim is to fully absorb the high intensity 400 GeV/c SPS beam. The BDF target complex would be located underground at a depth of about 10 m and is designed to contain most of the cascade generated by the primary beam interaction. Due to the high beam intensity delivered on target, the high density and high-Z composition of the target/dump, high activation of the material is expected, therefore evaluation of radiation protection risks is a crucial aspect for the design of this facility. In particular, high prompt and residual dose rates call for considerable shielding and remote interventions in the target area. Also the risk and environmental impact from air, water and soil activation heavily influence the design. In order to respect the applicable CERN radiation protection legislation regarding doses to personnel as well as the environmental impact, a preliminary radiological study was carried out. In order to validate the design of the BDF target, a scaled prototype was tested during 2018 in the SPS North Area at CERN. Preliminary results of radiological aspects for this test will be presented as well. To assess the above-mentioned radiation protection aspects, extensive simulations were performed with the FLUKA Monte Carlo particle transport code

    Analysis and Operational Feedback on the New Design of the High Energy Beam Dump in the CERN SPS

    No full text
    CERN's Super Proton Synchrotron (SPS) high-energy internal dump (Target Internal Dump Vertical Graphite, known as TIDVG) is required to intercept beams from 10² to 450 GeV. The equipment installed in 2014 (TIDVG#3) featured an absorbing core composed of different materials surrounded by a water-cooled copper jacket, which hold the UHV of the machine. An inspection of a previous equipment (TIDVG#2) in 2013 revealed significant beam induced damage to the aluminium section of the dump, which required imposing operational limitations to minimise the risk of reproducing this phenomenon. Additionally, in 2016 a vacuum leak was detected in the dump assembly, which imposed further limitations, i.e. a reduction of the beam intensity that could be dumped per SPS supercycle. This paper presents a new design (TIDVG#4), which focuses on improving the operational robustness of the device. Moreover, thanks to the added instrumentation, a careful analysis of its performance (both experimentally and during operation) will be possible. These studies will help validating technical solutions for the design of the future SPS dump to be installed during CERN's Long Shutdown 2 in 2020 (TIDVG#5)

    The SPS Beam Dump Facility

    No full text
    The proposed SPS beam dump facility (BDF) is a fixed-target facility foreseen to be situated at the North Area of the SPS. Beam dump in this context implies a target aimed at absorbing the majority of incident protons and containing most of the cascade generated by the primary beam interaction. The aim is a general purpose fixed target facility, which in the initial phase is aimed at the Search for Hidden Particles (SHiP) experiment. Feasibility studies are ongoing at CERN to address the key challenges of the facility. These challenges include: slow resonant extraction from the SPS; a target that has the two-fold objective of producing charged mesons as well as stopping the primary proton beam; and radiation protection considerations related to primary proton beam with a power of around 355 kW. The aim of the project is to complete the key technical feasibility studies in time for the European Strategy for Particle Physics (ESPP) update foreseen in 2020. This is in conjunction with the recommendation by the CERN Research Board to the SHiP experiment to prepare a comprehensive design study as input to the ESPP

    Status of the SRF systems at HIE-ISOLDE

    No full text
    The HIE-ISOLDE project has been approved by CERN in 2009 and gained momentum after 2011. The final energy goal of the upgrade is to boost the radioactive beams of REX-ISOLDE from the present 3 MeV/u up to 10 MeV/u for A/q up to 4.5. This is to be achieved by means of a new superconducting linac, operating at 101.28 MHz and 4.5 K with independently phased quarter wave resonators (QWR). The QWRs are based on the Nb sputtering on copper technology, pioneered at CERN and developed at INFN-LNL for this cavity shape. Transverse focusing is provided by Nb-Ti superconducting solenoids. The cryomodules hosting the active elements are of the common vacuum type. In this contribution we will report on the recent advancements of the HIE-ISOLDE linac technical systems involving SRF technology. The paper is focused on the cavity production, on the experience with the assembly of the first cryomodule (CM1), and on the results of the first hardware commissioning campaign
    corecore