The National Institute for Nuclear Physics (INFN) is developing, at the Laboratory of Accelerators and Applied Superconductivity (LASA Milan, Italy), five families of corrector magnets, from skew ...quadrupole up to dodecapole order, which will be installed in the interaction regions of the High-Luminosity Large Hadron Collider (LHC). These magnets are based on a superferric design, which allows a relatively simple, compact and easy-to-construct magnets. This activity takes place within the framework of a collaboration agreement between CERN and INFN. The magnets have been designed and prototype units have been built and tested for the sextupole, octupole, and decapole orders. Magnetic measurements have been performed in order to characterize the field quality, and to validate the design and construction. This paper presents the instruments and the approach for the magnetic measurements on the prototype magnets. Moreover, the results of measurements at cryogenic temperature, up to the nominal field level, are reported. The magnetic field quality, in terms of transfer function and field multipoles, is analysed as function of the excitation level. The iron saturation effects, which are a major concern of the selected design, are compared with the 3-D magnetic calculations and discussed in view of the construction of the series magnets to be integrated in the corrector package assembly.
Abstract
The yearly energy requirements of room temperature (RT) and superconducting (SC) magnet options of a new hadron therapy (HT) facility are compared. Special reference is made to the layouts ...considered for the proposed SEEIIST facility. Benchmarking with the RT CNAO HT centre in Pavia (Italy) was carried out. The energy comparison is centred on the different synchrotron solutions, assuming the same injector and lines in the designs. The beam current is 20 times higher than in present generation facilities: this allows efficient multi-energy extraction (MEE), which shortens the therapy treatment and is needed especially in the SC option, because of the slow magnet ramping time. Hence, power values of the facility in the traditional mode were converted into MEE ones, for a fair comparison between RT and SC magnets. Cryocoolers (c.c.) and a liquefier are also compared, for synchrotron refrigeration. This study shows that a RT facility in MEE mode requires the least average energy, followed by the SC synchrotron solution with a liquefier, while the most energy intensive solution is the SC one with c.c.
The quest for advancing science and technology continues with the Future Circular Collider (FCC), which requires 16 T bending dipoles to be installed along its 100 km tunnel to achieve a ...center-of-mass energy of 100 TeV, in its hadron-hadron version. The promising NbFormula OmittedSn technology for superconducting magnets presents a potential solution for large-scale production. In line with this, the European strategy for particle physics has urged for increased efforts in High Field Magnet R&D, specifically in constructing demonstrators for NbFormula OmittedSn technology. To address this call, the Istituto Nazionale di Fisica Nucleare (INFN) and CERN entered into an agreement to build a 1.5 m long cos-theta dipole in NbFormula OmittedSn, called Falcon Dipole (The Future Accelerator post-LHC Cos-theta Optimized NbFormula OmittedSn Dipole). The project aims to consolidate the fabrication process for NbFormula OmittedSn superconducting dipoles in the 12–14 T range, engaging industry partners in the initial stages of the R&D phase. This article provides a recall of the magnet design features and highlights the progress made in the development activities. Critical processes like the reaction treatment and the impregnation are discussed, with an emphasis on the test outcomes and the challenges faced. By taking these into account, plans for the production of the coils for the final configuration can be effectively formulated.
Aim
This randomized, controlled trial examined the medium-term effectiveness of online behavioral training in migraine self-management (oBT; N = 195) versus waitlist control (WLC; N = 173) on attack ...frequency, indicators of self-management (primary outcomes), headache top intensity, use of rescue medications, quality of life and disability (secondary outcomes).
Methods
An online headache diary following the ICHD-II and questionnaires were completed at baseline (T0), post-training (T1) and six months later (T2). Missing data (T1: 24%; T2: 37%) were handled by multiple imputation. We established effect sizes (ES) and tested between-group differences over time with linear mixed modelling techniques based on the intention-to-treat principle.
Results
At T2, attack frequency had improved significantly in oBT (−23%, ES = 0.66) but also in WLC (−19%; ES = 0.52). Self-efficacy, internal and external control in migraine management – and triptan use – improved only in oBT, however. This indicates different processes in both groups and could signify (the start of) active self-management in oBT. Also, only oBT improved migraine-specific quality of life to a sizable extent.
Conclusions
oBT produced self-management gains but could not account for improved attack frequency, because WLC improved as well. The perspective that BT effects develop gradually, and that online delivery will boost BT outreach, justifies further research.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In agreement with CERN the LASA laboratory of INFN (National Institute for Nuclear Physics) of Milan has carried out the industrial development of a novel type of magnet, for the High Order (HO) ...correctors of the High Luminosity - LHC (HL-LHC) project. These corrector magnets are based on a superferric design and will be installed in the new HL-LHC insertion regions for the ATLAS and CMS Experiments at CERN. These fifty-four correctors cover different harmonic order: from skew quadrupole up to dodecapole, and all assembled in six cold masses named Corrector Packages, a novelty for superferric in a collider. The first magnet batches have been already manufactured by industry and tested at LASA. Magnetic measurements have been performed at low current (at room temperature) as well as at operating current (4.2 K during cold tests at LASA). The measurements have been used as production monitoring and magnet acceptance. The measurement setup, based on a rotating coil system, is described including also the commissioning of the new PCB probe, supplied by CERN. To assess the suitability for collider operation the field multipoles and the transfer function for the various magnet types are reported in the paper. The results have been also compared to the 3-D model calculations.
In this review epidemiological studies concerning chronic benign pain among adults are discussed. To this end, studies focusing on chronic pain, reporting prevalences at a population or primary ...health care level, including subjects aged between 18 and 75 years have been collected and analyzed. Focus of analysis was on research methods, definitions of chronic benign pain used, and reported prevalences. Prevalences varied between 2% and 40% of the population. Nor method used (telephone survey, postal survey, nor definition of chronicity (>1 month; >3 months; >6 months) clearly explained the differences in prevalence in the various studies. Implications for future research are discussed.
INFN is developing at the LASA lab (Milano, Italy) the High Order (HO) corrector magnets for the High Luminosity-LHC (HL-LHC) project, which will equip the new interaction regions. All the HO ...correctors, from skew quadrupole to dodecapole, are based on a novel superferric design, never used so far in high energy colliders, which allows a relatively simple, modular, and easy way to construct a magnet. The series production is ongoing after the completion of the five prototypes program; all the 54 series magnets have been produced in the industry and the testing at LASA is ongoing. The delivery to CERN also started. We discuss the design optimizations introduced and the lessons learned during the first half of the series production. We also focus on the quality assurance plan, which allowed us to early detect non-conformities and monitor the learning curve. The testing station at LASA is fully operational, four magnets per cool down are tested. Each magnet is powered individually, and the magnetic measurement system, supplied by CERN, provides field quality and transfer function. We provide an overview of the performed tests and measurements, focusing on the test station's performance and quality of the measurements. Finally, we provide an outlook of the production completion, test plan and delivery to CERN.
INFN has developed at the LASA lab (Milano, Italy) the High Order (HO) corrector magnets for the High Luminosity-LHC (HL-LHC) project, which will equip the new interaction regions. All the HO ...correctors, from skew quadrupole to dodecapole, are based on a novel superferric design, never used so far in high energy colliders, which allows a relatively simple, modular, and easy way to construct a magnet. After the completion of the production of the 54 series magnets in industry, the powering of all the produced magnets has been achieved. The delivery to CERN and the assembly of the first cold mass started. Each magnet has been powered individually and most of them have also been magnetically characterized, the aggregate results are presented and discussed. The lessons learned during the production and the testing of the magnets are reported. The quality assurance and the procedures developed in during development and production in industry proved to be key points of the successful experience of the HO correctors development, together with the solid design. We also report the lessons learned during the experience of the series production of the HO correctors.
In the family of the High-Luminosity LHC high order correctors, the skew quadrupole was the most critical magnet as three assemblies with different solutions were needed to meet the design ...specifications. This paper summarizes the prototyping phase of the magnet, discussing the observed nonconformities, the subsequent root cause analyses, and the adopted solutions. A first-hand experience showed us the importance of adopting rigorous quality assurance methods for the electrical insulation, aimed at the early defect detection, and implementing a consistent measurement-to-simulations chain for the optimization of the coils mechanical support. The improvements discussed in the paper are integrated into the final magnet design for the series production of six skew quadrupole correctors.
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