Construction of the New Prototype of Main Quadrupole Cold Masses for the Arc Short Straight Sections of LHC

Each cold mass of the short straight sections in the eight LHC arcs will contain a 3.25 m long twin aperture quadrupole of a nominal gradient of 223 T/m. This magnet will be aligned in a 5.3 m long inertia tube together with auxiliary magnets on each end. On the quadrupole connection end either a pair of 38 cm long octupole or trim quadrupole magnets will be mounted, on the other end there will be combined sextupole-dipole correctors with a yoke length of 1.26 m. The powering of the main quadrupoles will be assured by two pairs of copper stabilized superconducting bus-bars placed inside the cold mass next to the bus-bars for the main dipole magnets. Each of the two quadrupole apertures will be connected to its quench protection diode. The construction of three prototypes has been entrusted to the CEA/Saclay laboratory, in the frame of the special French contribution to the LHC project. The first cold mass prototype has been completed and warm-measured for its multipole content at CEA. The second cold mass is presently under completion. The paper will review the experience with the development of the quadrupole coils and cold mass construction and gives the results of the first warm magnetic measurements. An outlook for the series manufacture of the 400 arc quadrupole magnets and their cold masses for the LHC machine will complete the report

The spread of iron in Central Asia: on the etymology of the word for “iron” in Iranian and Tocharian

Descriptive and Comparative Linguistic

Analysis of Warm Magnetic Measurements of the First Series-Design Prototypes of the LHC Main Quadrupoles

The room temperature magnetic measurements of the first series-design prototypes of the LHC main quadrupoles are analysed. Data relative to the collared coils and to the assembled cold mass are considered. The averages of the multipoles along the magnet axis are interpreted as the systematic components. The agreement with the nominal design is verified, and possible explanations for discrepancies with regard to the multipole allowed by symmetry are worked out. The standard deviations of the multipoles along the axis are interpreted as the random components. We show that the latter can be interpreted in terms of random movements of up to 25-35 µm of the coil blocks, because of components and assembly tolerances. A good correlation between measurements made on collared coil and the assembled cold mass is found. The influence on field quality of a systematic radial misalignment of the coil conductor is also evaluated

Triplicity and Physical Characteristics of Asteroid (216) Kleopatra

To take full advantage of the September 2008 opposition passage of the M-type asteroid (216) Kleopatra, we have used near-infrared adaptive optics (AO) imaging with the W.M. Keck II telescope to capture unprecedented high resolution images of this unusual asteroid. Our AO observations with the W.M. Keck II telescope, combined with Spitzer/IRS spectroscopic observations and past stellar occultations, confirm the value of its IRAS radiometric radius of 67.5 km as well as its dog-bone shape suggested by earlier radar observations. Our Keck AO observations revealed the presence of two small satellites in orbit about Kleopatra (see Marchis et al., 2008). Accurate measurements of the satellite orbits over a full month enabled us to determine the total mass of the system to be 4.64+/-0.02 10^18 Kg. This translates into a bulk density of 3.6 +/-0.4 g/cm3, which implies a macroscopic porosity for Kleopatra of ~ 30-50%, typical of a rubble-pile asteroid. From these physical characteristics we measured its specific angular momentum, very close to that of a spinning equilibrium dumbbell.Comment: 35 pages, 3 Tables, 9 Figures. In press to Icaru

Performance of Series-Design Prototype Main Quadrupoles for the LHC

After the successful construction of two first-generation prototypes of the main quadrupoles for the LHC, three series-design prototypes have been further manufactured at CEA-Saclay. Together with the sextupole-dipole corrector magnets and tuning quadrupoles, these twin-aperture main quadrupoles are assembled into the cold masses of the so-called short straight sections. Already during their fabrication, the collared coils and later the completed cold masses undergo warm magnetic measurements. Two of the main quadrupole cold masses have been mounted into their definitive machine cryostats and submitted to training and magnetic measurements. This paper presents the results of these cold tests by describing the quench behaviour, the transfer function in each of the apertures and the multipole components found at different levels of excitation. The field quality results, in cold conditions, will be compared to those measured at room temperatur

Launching of Series Fabrication of the LHC Main Quadrupoles

A collaboration agreement between CERN and CEA-Saclay resulted in the successful development and construction of prototypes of the LHC main superconducting quadrupole magnets and their assembly into cold masses. A call for tender was issued in October 1999 and led to the adjudication of a contract to ACCEL Instruments. A number of components will be provided by CERN to be used either directly by ACCEL for integration into the cold mass units or by sub-suppliers before delivery to ACCEL. During the series fabrication CEA's engineers and technicians, already experienced from their prototype work, will ensure the technology transfer and the technical follow up in the factory. ACCEL had to adapt two large fabrication halls to the needs of the magnet fabrication and the cold mass assembly. Procedures for a tight quality assurance and the logistics for the timely supply of components and a high production rate are being established in close collaboration by the three parties concerned

Performance of Prototypes and Start up of Series Fabrication of the LHC Arc Quadrupoles

The construction of three prototype arc quadrupoles for the LHC machine has been concluded successfully. These magnets underwent warm and cold magnetic measurements as well as many other tests, both in CEA-Saclay's laboratory and at CERN. Their training qualifies them for use in the LHC machine and their measured field quality points to only very minor corrections. An excellent correlation is found between warm and cold magnetic measurements. The prototype quadrupole design has been fully retained for the series fabrication of the 400 magnets and their cold masses by industry. This paper describes the main tests and measurement results of all three prototypes. It further explains the logistics for the manufacturing of the series of cold masses. These cold masses contain not only the main quadrupole but also different combinations of corrector magnets. Thus, together with variants imposed by the cryogenic configuration of the machine, 40 different types of cold masses have to be fabricated by the firm, to which the contract has been adjudicated

Biofuels from waste to road transport

Biofuels from Waste to Road (WASTE2ROAD) is an EU funded project under the Grant Agreement No. 818120 within the LC-SC3-RES-21-2018 call, “Development of next generation biofuels and alternative renewable fuel technologies for road transport”, as a Research and Innovation Action of the European Union’s Horizon 2020 Programme. The project started in the fall 2018 and will run for 4 years. In 2014, total waste production in the EU amounted to 2.5 billion tons. From this total only a limited (albeit increasing) share (36%) was recycled, while the rest was landfilled or burned, of which some 600 million tons could have been recycled or reused. Conversion of all sustainably available biogenic wastes and residues to biofuels could provide 27% of total transport fuel by 2050, achieving around 2.1 gigatons of CO2 emission reductions per year. The increasing demand for biofuels[1] implies the need for the transformation of diverse bio-resources into liquid fuels, and includes transformation of the biogenic part of municipal and industrial wastes into such biofuels. This clearly is a stepping stone to achieve the European goals[2] but it also poses challenges, such as 1) diversity and inhomogeneity of wastes throughout Europe (variable composition depending on the type of waste and geographical location), 2) the complexity of the conversion of wastes compared to fossil oils, 3) the technological aspects of co-refining and 4) high overall costs with moderate process performance. [1] https://www.iea.org/publications/freepublications/publication/Biofuels_Roadmap_WEB.pdf [2] https://europeanclimate.org/wp-content/uploads/2014/02/WASTED-final.pdf Please click Additional Files below to see the full abstract