Beam Line Design for the CERN Hiradmat Test Facility

The LHC phase II collimation project requires beam shock and impact tests of materials used for beam intercepting devices. Similar tests are also of great interest for other accelerator components such as beam entrance/exit windows and protection devices. For this purpose a dedicated High Radiation Material test facility (HiRadMat) is under study. This facility may be installed at CERN at the location of a former beam line. This paper describes the associated beam line which is foreseen to deliver a 450 GeV proton beam from the SPS with an intensity of up to 3×10**13 protons per shot. Different beam line designs will be compared and the choice of the beam steering and diagnostic elements will be discussed, as well as operational issues

Summary of the CERN Workshop on Materials for Collimators and Beam Absorbers

The main focus of the workshop was on collimators and beam absorbers for (mainly) High Energy Hadron Accelerators, with the energy stored in the beams far above damage limit. The objective was to better understand the technological limits imposed by mechanisms related to beam impact on materials. The idea to organise this workshop came up during the High Intensity High Brightness Hadron Beams, ICFA-HB2006 in Japan [1]. The workshop was organised 3-5 September 2007 at CERN, with about 60 participants, including 20 from outside CERN. About 30 presentations were given [2]. The event was driven by the LHC challenge, with more than 360 MJoule stored in each proton beam. The entire beam or its fraction will interact with LHC collimators and beam absorbers, and with the LHC beam dump blocks. Collimators and beam absorbers are also of the interest for other labs and accelerators: - CERN: for the CNGS target, for SPS beam absorbers (extraction protection) and collimators for protecting the transfer line between SPS and LHC - GSI: SIS18 and SIS 100/200, Super-FRS target, HED experiments, Antiproton target, etc. - Fermilab: Tevatron and Main Injector collimation systems; neutrino production targets (MINOS, SNuMI, NOVA); antiproton production targets; pion production targets and beam absorbers for neutrino factories and muon colliders - ILC: positron production targets, beam absorbers and collimators for a beam delivery system

Protection of the LHC against Unsynchronised Beam Aborts

An unsynchronised beam abort in the LHC could damage downstream accelerator components, in particular the extraction septum magnets, the experimental low-beta triplet magnet apertures and the tertiary collimators. Although the LHC beam dumping system includes design features to minimise their frequency, such unsynchronised aborts cannot be excluded. A system of protection devices comprising fixed and moveable diluters and collimators will protect the downstream LHC aperture from the misdirected bunches in case of such a failure. The sources of unsynchronised aborts are described, together with the requirements and design of the protection devices and their expected performance. The accompanying operational requirements and envisaged solutions are discussed, in particular the problem of ensuring the local orbit at the protection devices

Spatial Heterogeneity in the Abundance and Fecundity of Arctic Mosquitoes

The abundance of mosquitoes is strongly influenced by biotic and abiotic factors that act on the immature (aquatic) and adult (terrestrial) life stages. Rapid changes in land use and climate, which impact aquatic and terrestrial mosquito habitat, necessitate studying the ecological mechanisms, and their interplay with the changing environment, that affect mosquito abundance. These data are crucial for anticipating how environmental change will impact their roles as pests, disease vectors, and in food webs. We studied a population of Arctic mosquitoes (Aedes nigripes, Diptera: Culicidae) in western Greenland, a region experiencing rapid environmental change, to quantify spatial variation in adult abundance and reproduction. Using sweep nets, we collected about sevenfold more mosquitoes within the town of Kangerlussuaq and within a low‐elevation tundra valley compared to three other tundra locations. Dissections of adult female mosquitoes revealed that only 17% were gravid overall, with a range of 7–43% among sites. If gravid, mosquitoes matured an average of 60 eggs per individual—more in larger females. We found no indication of autogenous egg development. Analyses using our field data indicated that spatial variation in adult fecundity and survival of immatures could each account for a 10‐fold range in the per capita growth of mosquito populations. The availability of vertebrate hosts and aquatic habitat is changing in many parts of the Arctic and can be expected to influence Arctic mosquito abundance. In the Arctic, and elsewhere, life‐history data from natural populations of mosquitoes will significantly aid in understanding controls on the abundance of these globally ubiquitous insects

Beam Halo on the LHC TCDQ Diluter System and Thermal Load on the Downstream Superconducting Magnets

The moveable single-jawed graphite TCDQ diluter must be positioned very close to the circulating LHC beam in order to prevent damage to downstream components in the event of an unsynchronised beam abort. A two-jawed graphite TCS.IR6 collimator forms part of the TCDQ system. The requirement to place the jaws close to the beam means that the system can intercept a substantial beam halo load. Initial investigations indicated a worryingly high heat load on the Q4 coils. This paper presents the updated load cases, shielding and simulation geometry, and the results of simulations of the energy deposition in the TCDQ system and in the downstream superconducting Q4 magnet. The implications for the operation of the LHC are discussed

Design, Fabrication and Initial Testing of a Large Bore Single Aperture 1 m Long Superconducting Dipole Made with Phenolic Inserts

In the framework of the LHC magnet development programme, a large bore single aperture 1-meter long superconducting dipole has been built in collaboration with HOLEC. The magnet features a single layer coil wound using the LHC main dipole outer layer cable, phenolic inserts, and a keyed two part structural iron yoke. This paper presents the magnetic and mechanical design and optimisation of the magnet. We describe the coil winding and curing, and present the construction and assembly procedures. Finally we report on the mechanical behaviour during assembly and cooling, and present the magnet training behaviour

Testing of the large bore single aperture 1-meter superconducting dipoles made with phenolic inserts

Two identical single aperture 1-metre superconducting dipoles have been built in collaboration with HMA Power Systems and tested at CERN. The 87.8 mm aperture magnets feature a single layer coil wound using LHC main dipole outer layer cable, phenolic spacer type collars, and a keyed two part structural iron yoke. The magnets are designed as models of the D1 separation dipole in the LHC experimental insertions, whose nominal field is 4.5 T at 4.5 K. In this report we present the test results of the two magnets at 4.3 K and 1.9 K

Duurzaam doen! Leren in vitale coalities; Monitoring en evaluatie van de programma's Leren voor Duurzame Ontwikkeling en Natuur- en Milieueducatie

Monitoring en evaluatie van de programma's "leren voor duurzame ontwikkeling" en "natuur- en milieueducatie". Binnen het programma NME heeft het instrument 'arrangementenmodel' een centrale plaats ingenomen. Binnen de arrangementen zijn nieuwe samenwerkingsvormen tussen NME-organisaties en blijvende contacten met nieuwe partners ontstaan, en wordt er meer aangesloten bij de bestuurlijke agenda van gemeenten. Vraagarticulatie en verankering van deze nieuwe manier van werken blijven aandachtspunten voor de toekomst

Tussenrapportage evaluatie programma's Leren voor Duurzame Ontwikkeling en Natuur- en Milieueducatie, 2008-2011

Het programma LvDO stond in de periode 2008 tot 2011 voor de uitdaging duurzaamheid te verankeren in dagelijkse praktijken. Het programma continueerde de strategie uit de vorige programmaperiode om top-down aan de beïnvloeding van systemen en bottom-up aan de ondersteuning van netwerken van professionals te werken. Daarnaast richtte het programma zich op kennisontsluiting, voornamelijk in de vorm van kennisontwikkeling en kenniscirculatie. Deze strategie werd gericht op de drie pijlers van het programma: Onderwijs, Rijksoverheid en Decentrale overheden. Vanaf 2008 is het concept ‘arrangement’ geïntroduceerd in de NME-sector. Een arrangement is een coalitie waarin aanbieders, vragende, bestuurlijke en maatschappelijke partijen samenwerken

Duurzaam doen! Leren in vitale coalities; Monitoring en evaluatie van de programma's Leren voor Duurzame Ontwikkeling en Natuur- en Milieueducatie

Monitoring en evaluatie van de programma's "leren voor duurzame ontwikkeling" en "natuur- en milieueducatie". Binnen het programma NME heeft het instrument 'arrangementenmodel' een centrale plaats ingenomen. Binnen de arrangementen zijn nieuwe samenwerkingsvormen tussen NME-organisaties en blijvende contacten met nieuwe partners ontstaan, en wordt er meer aangesloten bij de bestuurlijke agenda van gemeenten. Vraagarticulatie en verankering van deze nieuwe manier van werken blijven aandachtspunten voor de toekomst