Energy saving magnets for beam lines Rossi, L.; Mariotto, S.; Sorti, S.
Journal of physics. Conference series,
01/2024, Letnik:
2687, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Abstract
Beam lines magnets for high rigidity particles can have a large power dissipation. In presence of a high duty cycle, this translates in a considerable amount of energy waste. The call for ...sustainability of large research infrastructures, like particle accelerator centers, and the recent increase of the cost of energy, require to take measures to reduce the energy consumption, even at cost of moderate investment. A study program called ESABLIM (Energy SAving Beam LIne Magnets) has been set up at the LASA lab of University and INFN Milano, aimed at revamping existing normal-conducting magnets for beam lines with the target of cutting the peak power by a factor 10 to 20 and reducing the energy consumption by factor 5 or more. The idea is to replace the water cooled coils of iron-dominated magnets with new superconducting coils cooled at 10-20 K by means of a cryocooler, while to reusing the iron yoke pole assembly. We envisage using MgB2 for its moderate cost, however, high temperature superconductors (HTS) will also be considered as conductor. We present the first advanced design for revamping of a large bending dipole in a hadron therapy center, and the conceptual design for magnets in a nuclear physics laboratory and we try to define the domain where this transformation of normal-conducting into super-ferric magnets can be technically and economically advantageous.
Background
Serum neurofilament light chain (sNfL) may be used as a biological marker of disease progression in multiple sclerosis (MS), although longitudinal studies correlating cognitive deficits to ...sNfL are limited.
Objective
To longitudinally investigate the relation between cognitive dysfunction, sNfL and MRI brain volume in a relapsing remitting MS patients.
Methods
18 MS patients (9 males and 9 females, mean age 45 years, mean education 12.6 years) all prescribed with interferon beta 1a (44 mcg 3 times per week), are longitudinally evaluated by means of annual clinical exam with EDSS, neuropsychological evaluation with Brief repeatable battery (BRB) and Delis Kaplan Executive function test (DKEFS), dosage of sNfL (SIMOA) and MRI.
Results
Here are reported the results of 1 year follow-up. A significantly higher sNfL in MS compared to healthy controls and higher sNfL in patients with greater cognitive impairment were found. Cognitive Impairment Index, memory, executive function tests correlated with sNfL. Gray matter volume resulted unchanged at 1-year follow-up; a weak correlation between some tests’ score and selective cortical brain areas was found.
Conclusion
Our longitudinal pilot study confirms that sNfL are related to cognitive abilities, confirming data of other authors from retrospective studies.
Magnets for a Muon Collider Fabbri, S.; Bottura, L.; Quettier, L. ...
Journal of physics. Conference series,
01/2024, Letnik:
2687, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Abstract
The renewed interest for a muon collider has motivated a thorough analysis of the accelerator technology required for this collider option at the energy frontier. Magnets, both normal and ...superconducting, are among the crucial technologies throughout the accelerator complex, from production, through acceleration and collision. In this paper we initiate a catalog of magnet specifications for a muon collider at 10TeV center-of-mass. We take the wealth of work performed within the scope of the US-DOE Muon Accelerator Program as a starting point, update it with present demands for the increased energy reach, and focus on the magnet types and variants with the most demanding performance. These represent well the envelope of issues and challenges to be addressed by future design and development. We finally give a first and indicative selection of suitable magnet technology, taking into account both established practices as well as the perspective evolution in the field of accelerator magnets.
Introduction
Paclitaxel-induced peripheral neurotoxicity (PIPN) typically manifests as a predominantly sensory axonopathy. Nerve conduction studies (NCS) represent the gold standard method to ...quantify axonal impairment in PIPN. Serum neurofilament light chain (sNfL) levels are emerging biomarkers for quantifying axonal damage in peripheral neuropathies. To date, the association between NCS abnormalities and sNfL levels during paclitaxel-based chemotherapy has not been specifically addressed.
Methods
We prospectively conducted longitudinal measurement of sNfL levels in 27 chemotherapy-naïve breast cancer patients and correlated conventional NCS recordings with sNfL in 22 of them, before (T0) and after (T1) 12 cycles of weekly paclitaxel-based therapy.
Results
PIPN was diagnosed in 24/27 patients (88%) after completion of the 12-week paclitaxel-based chemotherapy regimen. Serum NfL levels (pg/mL) were significantly higher at T1 compared to T0 (T0: 18.50 ± 12.88 vs T1: 255.80 ± 194.16;
p
< 0.001). The increase of sNfL levels at T1 significantly correlated with the decrease or abolishment of amplitudes recorded from the sural nerve (
r
= 0.620;
p
= 0.0035), sensory radial (
r
= 0.613;
p
= 0.005), sensory ulnar (
r
= 0.630;
p
= 0.005), and peroneal motor (
r
= 0.568;
p
= 0.024) nerves.
Conclusion
sNfL levels proportionally increase during chemotherapy administration and significantly correlate with NCS axonal abnormalities in patients with PIPN. A multimodal testing approach employing both sNfL and NCS might improve the PIPN diagnostic accuracy.
To meet the milestones set by the High-Luminosity LHC (HL-LHC) project, the integration of new inner triplet magnet circuits is vital for enhancing the focusing of the particle beams at ATLAS and ...CMS. In addition to the Nb 3 Sn quadrupole magnets, high-order Nb-Ti magnets are required for field correction. This comprises self-protected magnets with six, eight, ten, and twelve poles, which also come in skewed variants. The simulation program LEDET was developed as part of the STEAM framework and is now applied to study quench transients in HL-LHC magnets. The electromagnetic and thermal transients occurring after a quench are simulated and validated with experiments at different current levels conducted by LASA (INFN). For the models, the three-dimensional geometry is accurately replicated and for each magnet the conductor parameters of each coil are set according to measurements. After discussing the various assumptions of the model, a simulation study is conducted to investigate the influence of the unknown quench location and inter-filament coupling losses. The developed models of each magnet show satisfactory accuracy and are predictive for different current levels. The models are then used to analyse the simulated hot-spot temperatures and peak voltages-to-ground, which cannot be easily measured. It is concluded that the protection strategy is effective.
The Superconducting Ion Gantry (SIG) project is the contribution from INFN (the Italian National Institute for Nuclear Physics) to the international SIGRUM project with the aim of exploring new ...technological solutions for the critical elements of a 430 MeV/u carbon ion gantry. The project includes the design and construction of a cos<inline-formula><tex-math notation="LaTeX">\theta</tex-math></inline-formula> 4 T superconducting dipole demonstrator magnet whose main scope is to prove the feasibility of winding and assembling an accelerator magnet type with a relatively small radius of curvature (1.65 m). In addition to the complexity due to the curvature, the target field ramp rate is 0.4 T/s and the cooling system must not adopt liquid helium. This paper discusses the design activities carried out in the last year on the electromagnetic and thermal domains and reports on the present concepts and infrastructure for the first winding trials.
Canted Cosine Theta layout for accelerator magnets is a very attractive since such magnets can be manufactured and assembled without big tooling, and with a relatively modest number of parts and ...tools. In the frame of European Horizon2020 funds, two collaborations, HITRI plus and I.FAST, are developing a CCT design, of 80 mm free bore, 4 T central dipole field, and 0.4 T/s ramp-rate. This magnet is expected to be the bending element of a gantry, to control the beam delivery in therapy with ions (hadrontherapy). The paper illustrates first a comparison between CCT and more classical cosine theta layout, followed by the comparison between Nb-Ti, Nb 3 Sn, MgB 2 , and HTS tapes coils. Relevant requirement for the magnets of this study is to be operated at low current, to limit the heat generation, in sight of a liquid-free cooling system. The results of the comparison is then applied to the design of two magnet demonstrators. Both adopt a low-losses Nb-Ti rope, consistently with the need for keeping the heat generation as low as possible. The first is a straight combined function dipole-quadrupole, while the second is a curved CCT dipole. The paper concludes with the first manufacturing tests for the CCT formers, for which aluminium -bronze, stainless steel and charged PEEK polymer are being explored as basic material.
A collaboration between CERN, CNAO, INFN, and MedAustron has been formed aiming at designing a light rotating gantry suitable for hadron therapy based on 430 MeV/n carbon ion beams. After a first ...design for a 3 T dipole field, as the backbone of the gantry magnetic system, now the collaboration is looking at an alternative design, for at least 4 T field with a faster ramp rate. The magnet is designed according to the cosθ layout to be wound with Nb-Ti superconducting Rutherford cable. One of the main challenges is the very small curvature radius of 1.65 m with a relatively large aperture, of 70-90 mm. Another challenge is the use of indirect cooling despite the cycling operation of 0.4 T/s. The paper reports the preliminary investigation for a 4.5 T dipole. The design will be followed by the construction of a 1 m long demonstrator to be manufactured and tested at INFN (LASA laboratory) in about three years. The conductor is a Rutherford cable of 2.6 µm Nb-Ti filament size, embedded in a Cu-Mn alloy matrix. The resulting gantry is very compact: the collaboration is working on integration between gantry structure and magnets to allow reducing the rotating weight in the range 50-80 tons, which is a factor 4 to 5 less than the present state-of-the-art.
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