HTS Dipole Insert Developments Rey, J.-M; Devaux, M.; Bertinelli, F. ...
IEEE transactions on applied superconductivity,
06/2013, Letnik:
23, Številka:
3
Journal Article, Conference Proceeding
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Future accelerator magnets will need to reach a magnetic field in the 20 T range. Reaching such a magnetic field is a challenge only reachable using high temperature superconductor (HTS) material. ...The high current densities and stress levels needed to satisfy the design criterion of such magnets make YBaCuO superconductor the most appropriate candidate especially when produced using the IBAD route. The HFM EUCARD program is aimed at designing and manufacturing a dipole insert made of HTS material generating 6 T inside a Nb 3 Sn dipole of 13 T at 4.2 K. In the HTS insert, engineering current densities higher than 250 MA/m 2 under 19 T are required to reach the performances. The stress level is consequently very high. The insert protection is also a critical issue as HTS shows low quench propagation velocity. The coupling with the Nb 3 Sn dipole makes the problem even more difficult. The magnetic and mechanical designs of the HTS insert will be presented as well as the technological developments underway to realize this compact dipole insert.
The synchrotron SIS300 is a fundamental component of the FAIR facility under construction at the GSI laboratory in Darmstadt. The acceleration of high intensity proton and heavy ion beams requires ...4.5 T magnets, up to 7.8 m long, to be ramped up at a rate of 1 T/s. These challenging magnets have also the particular characteristic to be geometrically curved with a sagitta of 114 mm. To demonstrate the feasibility of curved fast cycled cos-theta dipoles, R&D activities were performed at the Italian National Institute of Nuclear Physics. Important steps of the R&D have been: 1) the development of a low loss superconducting Rutherford cable; 2) the construction of coil winding models for assessing the constructive feasibility of curved coils; and 3) the construction and tests of a complete model magnet composed of a cold mass enclosed in its horizontal cryostat. During 2012 the cold mass was tested at Italian National Institute of Nuclear Physics-LASA in a vertical cryostat. The paper discusses the main issues of the R&D activity from design to manufacture, results, future developments, and future perspectives.
The Italian Institute for Nuclear Physics is working on the development of fast cycled dipoles for the Facility for Antiproton and Ion Research SIS300 synchrotron at Gesellschaft für ...Schwerionenforschung, Darmstadt. In this framework the development of high current and low ac loss superconducting wires is an important step of the R&D. The main technique to attain these features is to develop fine filaments for the strands and to design suitable resistive barriers among filament islands within the strands. In this paper, we study a newly developed wire in terms of critical currents and ac losses. The critical current is obtained from magnetization cycle and direct transport current. The ac loss mechanisms caused by the interfilament electromagnetic coupling is related to the ρ et , the transverse resistance between adjacent filaments. We measure ρ et through ac susceptibility technique.
The SIS300 is one of the two fast ramped synchrotrons of the future FAIR facility to be built at the site of GSI at Darmstadt, Germany. Planned to be installed during the second phase of FAIR, ...preliminary R&D work has to be carried out now to be ready to build up the machine later on without delay. Some remarkable results have been achieved over the last years concerning the development of the magnets for this machine, which are of superconducting cos(θ) type. For example a low loss Rutherford cable with stainless steel core and small filament wires has been developed. Also prototype magnets, dipoles as well as quadrupoles, have been manufactured and tested successfully. The experiences with the first curved dipole in the frame of the DISCORAP project showed the need for some changes in the design of the collared coil. Such a new collared coil is under construction now in the frame of the European CRISP project. The presentation will show the lessons learned from the DISCORAP project and the actual status of the CRISP coil.
The INFN (Istituto Nazionale di Fisica Nucleare, Italy) has launched in 2006 the DISCORAP (DIpoli SuperCOnduttori RApidamente Pulsati, or fast-pulsed superconducting dipoles) project which foresees ...the design, manufacture and test of a fast cycled (1 T/s) 4.5 T, cos θ , dipole model for the SIS 300 synchrotron of the FAIR (Facility for Antiproton and Ion Research) facility at GSI (Darmstadt, Germany). This magnet is now close to completion at ASG company (Genova, Italy); it is based on a Rutherford cable, manufactured by Luvata Superconductors, which incorporates several technologies to reduce the AC losses, namely a Nb-Ti filament diameter around 3 μm, Cu 0.5wt%Mn interfilamentary matrix and a Rutherford cable with stainless steel core. The development of the Rutherford foresees two subsequent generations of Rutherford cables, aimed to reach the demanding goals of the SIS-300 specifications in steps. In this paper we present the results of the manufacture of the first generation Rutherford cable, and the assessment of its electromagnetic performances, including critical current density, twist pitch impact on critical current degradation, filament hysteresis and de formation, transverse resistivity, Cu-Mn paramagnetism.
The Facility for Anti-proton and Ion Research (FAIR), under development at GSI, includes the synchrotron SIS300, so called because the magnetic rigidity is 300 Tm. In order to reach the required high ...intensities of proton and heavy ions beams, the bending dipole magnets have to be pulsed from the injection magnetic field of 1.5 T up to 4.5 T maximum field at the rate of 1 T/s. These 7.8 m long magnets have cos θ shaped coils with a 100 mm bore and the particular characteristic to be geometrically curved, with a sagitta of 112.9 mm. These challenging requirements triggered R&D activities, aimed at the development of suitable construction technologies for fast ramped curved coils. The heart of the R&D program is the construction of a 3.9 m long model. The paper discusses the main problems faced during the design and the construction of the cold mass, mainly covering the aspects related to the manufacture.
A MgB2 superferric racetrack magnet Musenich, R; Sorbi, M; Tavilla, G ...
Superconductor science & technology,
10/2008, Letnik:
21, Številka:
10
Journal Article
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A magnesium diboride, cryogen-free, H-dipole magnet with cold iron yoke was constructed and tested. The racetrack coil, 48 cm long, was wound with 350 m of nickel-clad, copper-MgB2 tape. The iron ...yoke forms a 2.6 cm gap. The magnet was connected to a cryocooler and tested at different temperatures ranging between 8.5 and 24 K. The maximum current, 263 A, was reached, without training, at 8.5 K. The corresponding field in the gap was 2.35 T.
Computerized diary measurement of pain, disability and psychological adaptation was performed four times a day for 4 weeks in 80 patients with various duration of unexplained pain. Reported are (1) ...the temporal characteristics and stability of pain report during the 4-week measurement period, (2) the association between pain duration and pain report, disability and general psychopathology, and (3) the accordance between diary assessment versus questionnaire assessment of pain, disability and psychological adaptation. No evidence of instrument reactivity was found: pain report was stable across the 4-week period. However, pain report appeared to be highly variable both between and within days. About half the patients showed a clear increasing trend in pain during the day. Several differences were found between subgroups of patients varying in pain duration. Patients with less than 6 months of pain reported significantly less pain intensity, disability and fatigue than patients whose pain persisted for more than 6 months. Pain coping and responses to pain behaviors by the spouse also differed for the subgroups: longer pain duration was associated with increased catastrophizing and solicitous responses from the spouse. Comparison of scores obtained with diary versus questionnaire assessment indicated moderate correlations for most variables. Retrospective (questionnaire) assessment of pain intensity yielded significantly higher pain scores than diary assessment.
Objectives. Emotion regulation is hypothesized to be related to health through neuroendocrine–immune changes. This study examined the role of the neuroendocrine variables 24-h urinary cortisol and ...noradrenaline, and the immune variable serum interleukin 6 as mediators between emotion regulation styles and health (perceived health and disease activity: erythrocyte sedimentation rate (ESR) and Thompson joint score). Methods. Sixty patients with rheumatoid arthritis (mean age 59.0±11.2 yr; 38 female) participated. Results. Emotion regulation was not associated with immune functioning or disease activity, but it was somewhat related to neuroendocrine functioning: one of the emotion regulation styles, ambiguity, was related to noradrenaline in women (r = 0.39) but not in men. The indicators of neuroendocrine functioning (cortisol and noradrenaline) were correlated (r = 0.40), as were indicators of immune functioning (interleukin 6) and inflammatory activity (ESR; r = 0.53), but analyses did not indicate a role of these physiological variables in mediating between emotion regulation and health: neuroendocrine variables were not related to interleukin 6 or ESR, and none of the physiological parameters was correlated with joint score or perceived health. Conclusions. To examine whether the proposed mediational processes apply to individual patients, a longitudinal within-subjects design is needed. In our cross-sectional study, emotion regulation was somewhat related to neuroendocrine functioning, but our study did not uncover a potential mediational role of cortisol, noradrenaline or interleukin 6 in the relationship between emotion regulation and health in rheumatoid arthritis.
This paper presents the 2D design of the SIS300 synchrotron dipole of the FAIR facility at GSI. The dipole has a length of 7.8 m, a field of 4.5 T, in a 100 mm bore, and is ramped at 1 T/s. The ...studies are performed by INFN (Frascati, Genova and Milano-LASA) in a R&D collaboration with GSI. The program started in 2006 (DISCORAP) and has as a final goal the construction and test of a prototype. Particular emphasis is given to the study of the field quality and of the losses during the ramping of the magnet. Some calculation methods and different codes for magnet design are evaluated and compared.
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