511 results on '"Brouwer L"'
Search Results
2. Electromagnetic modeling and science reach of DMRadio-m$^3$
- Author
-
DMRadio Collaboration, AlShirawi, A., Bartram, C., Benabou, J. N., Brouwer, L., Chaudhuri, S., Cho, H. -M., Corbin, J., Craddock, W., Droster, A., Foster, J. W., Fry, J. T., Graham, P. W., Henning, R., Irwin, K. D., Kadribasic, F., Kahn, Y., Keller, A., Kolevatov, R., Kuenstner, S., Kurita, N., Leder, A. F., Li, D., Ouellet, J. L., Pappas, K. M. W., Phipps, A., Rapidis, N. M., Safdi, B. R., Salemi, C. P., Simanovskaia, M., Singh, J., van Assendelft, E. C., van Bibber, K., Wells, K., Winslow, L., Wisniewski, W. J., and Young, B. A.
- Subjects
High Energy Physics - Experiment ,Astrophysics - Cosmology and Nongalactic Astrophysics ,High Energy Physics - Phenomenology ,Physics - Instrumentation and Detectors - Abstract
DMRadio-m$^3$ is an experiment that is designed to be sensitive to KSVZ and DFSZ QCD axion models in the 10-200 MHz (41 neV$/c^2$ - 0.83 $\mu$eV/$c^2$) range. The experiment uses a solenoidal dc magnetic field to convert an axion dark-matter signal to an ac electromagnetic response in a coaxial copper pickup. The current induced by this axion signal is measured by dc SQUIDs. In this work, we present the electromagnetic modeling of the response of the experiment to an axion signal over the full frequency range of DMRadio-m$^3$, which extends from the low-frequency, lumped-element limit to a regime where the axion Compton wavelength is only a factor of two larger than the detector size. With these results, we determine the live time and sensitivity of the experiment. The primary science goal of sensitivity to DFSZ axions across 30-200 MHz can be achieved with a $3\sigma$ live scan time of 3.7 years., Comment: 14 pages, 6 figures
- Published
- 2023
3. Conceptual design of 20 T hybrid accelerator dipole magnets
- Author
-
Ferracin, P., Ambrosio, G., Anerella, M., Arbelaez, D., Brouwer, L., Barzi, E., Cooley, L., Cozzolino, J., Fajardo, L. Garcia, Gupta, R., Juchno, M., Kashikhin, V. V., Kurian, F., Marinozzi, V., Novitski, I., Rochepault, E., Stern, J., Vallone, G., Yahia, B., and Zlobin, A. V.
- Subjects
Physics - Accelerator Physics - Abstract
Hybrid magnets are currently under consideration as an economically viable option towards 20 T dipole magnets for next generation of particle accelerators. In these magnets, High Temperature Superconducting (HTS) materials are used in the high field part of the coil with so-called insert coils, and Low Temperature Superconductors (LTS) like Nb3Sn and Nb-Ti superconductors are used in the lower field region with so-called outsert coils. The attractiveness of the hybrid option lays on the fact that, on the one hand, the 20 T field level is beyond the Nb3Sn practical limits of 15-16 T for accelerator magnets and can be achieved only via HTS materials; on the other hand, the high cost of HTS superconductors compared to LTS superconductors makes it advantageous exploring a hybrid approach, where the HTS portion of the coil is minimized. We present in this paper an overview of different design options aimed at generating 20 T field in a 50 mm clear aperture. The coil layouts investigated include the Cos-theta design (CT), with its variations to reduce the conductor peak stress, namely the Canted Cos-theta design (CCT) and the Stress Management Cos-theta design (SMCT), and, in addition, the Block-type design (BL) including a form of stress management and the Common-Coil design (CC). Results from a magnetic and mechanical analysis are discussed, with particular focus on the comparison between the different options regarding quantity of superconducting material, field quality, conductor peak stress, and quench protection.
- Published
- 2023
- Full Text
- View/download PDF
4. An Initial Look at the Magnetic Design of a 150 mm Aperture High-Temperature Superconducting Magnet With a Dipole Field of 8 to 10 T
- Author
-
Wang, X, Arbelaez, D, Brouwer, L, Caspi, S, Ferracin, P, Fajardo, L Garcia, Gourlay, S, Higley, H, Juchno, M, Marchevsky, M, Pong, I, Prestemon, S, Fernandez, JL Rudeiros, Sabbi, G, Shen, T, Teyber, R, Vallone, G, van der Laan, D, and Weiss, J
- Subjects
Nuclear and Plasma Physics ,Physical Sciences ,Arc magnet ,muon collider ,REBCO ,high-temperature superconducting magnet ,Condensed Matter Physics ,Electrical and Electronic Engineering ,Materials Engineering ,General Physics ,Electrical engineering ,Condensed matter physics - Abstract
High-temperature superconducting REBa{2} Cu{3}O{7-x} (rebco) conductors have the potential to generate a high magnetic field over a broad temperature range. The corresponding accelerator magnet technology, still in its infancy, can be attractive for future energy-frontier particle colliders such as a multi-TeV muon collider. To help develop the technology, we explore the requirements and potential characteristics of a rebco magnet, operating at 4.2 or 20 K, with a dipole field of 8-10 T in a clear aperture of 150 mm. We use the canted \cos \theta magnet configuration to reduce the electromagnetic stresses on the conductors. We present the resulting dipole fields, field gradients for combined-function cases, conductor stresses, magnet dimensions and conductor lengths. We also discuss the conductor performance that is required to achieve the target dipole field at 4.2 and 20 K. The information can provide useful input to the development of rebco magnet and conductor technology for collider-ring magnets in a muon collider.
- Published
- 2023
5. Towards 20 T Hybrid Accelerator Dipole Magnets
- Author
-
Ferracin, P., Ambrosio, G., Arbelaez, D., Brouwer, L., Barzi, E., Cooley, L., Fajardo, L. Garcia, Gupta, R., Juchno, M., Kashikhin, V., Marinozzi, V., Novitski, I., Rochepault, E., Stern, J., Zlobin, A., and Zucchi, N.
- Subjects
Physics - Accelerator Physics - Abstract
The most effective way to achieve very high collision energies in a circular particle accelerator is to maximize the field strength of the main bending dipoles. In dipole magnets using Nb-Ti superconductor the practical field limit is considered to be 8-9 T. When Nb3Sn superconductor material is utilized, a field level of 15-16 T can be achieved. To further push the magnetic field beyond the Nb3Sn limits, High Temperature Superconductors (HTS) need to be considered in the magnet design. The most promising HTS materials for particle accelerator magnets are Bi2212 and REBCO. However, their outstanding performance comes with a significantly higher cost. Therefore, an economically viable option towards 20 T dipole magnets could consist in an hybrid solution, where both HTS and Nb3Sn materials are used. We discuss in this paper preliminary conceptual designs of various 20 T hybrid magnet concepts. After the definition of the overall design criteria, the coil dimensions and parameters are investigated with finite element models based on simple sector coils. Preliminary 2D cross-section computation results are then presented and three main layouts compared: cos-theta, block, and common-coil. Both traditional designs and more advanced stress-management options are considered., Comment: arXiv admin note: substantial text overlap with arXiv:2203.13985
- Published
- 2022
- Full Text
- View/download PDF
6. Projected Sensitivity of DMRadio-m$^3$: A Search for the QCD Axion Below $1\,\mu$eV
- Author
-
DMRadio Collaboration, Brouwer, L., Chaudhuri, S., Cho, H. -M., Corbin, J., Craddock, W., Dawson, C. S., Droster, A., Foster, J. W., Fry, J. T., Graham, P. W., Henning, R., Irwin, K. D., Kadribasic, F., Kahn, Y., Keller, A., Kolevatov, R., Kuenstner, S., Leder, A. F., Li, D., Ouellet, J. L., Pappas, K., Phipps, A., Rapidis, N. M., Safdi, B. R., Salemi, C. P., Simanovskaia, M., Singh, J., van Assendelft, E. C., van Bibber, K., Wells, K., Winslow, L., Wisniewski, W. J., and Young, B. A.
- Subjects
High Energy Physics - Experiment ,High Energy Physics - Phenomenology ,Physics - Instrumentation and Detectors - Abstract
The QCD axion is one of the most compelling candidates to explain the dark matter abundance of the universe. With its extremely small mass ($\ll 1\,\mathrm{eV}/c^2$), axion dark matter interacts as a classical field rather than a particle. Its coupling to photons leads to a modification of Maxwell's equations that can be measured with extremely sensitive readout circuits. DMRadio-m$^3$ is a next-generation search for axion dark matter below $1\,\mu$eV using a $>4$ T static magnetic field, a coaxial inductive pickup, a tunable LC resonator, and a DC-SQUID readout. It is designed to search for QCD axion dark matter over the range $20\,\mathrm{neV}\lesssim m_ac^2\lesssim 800\,\mathrm{neV}$ ($5\,\mathrm{MHz}<\nu<200\,\mathrm{MHz}$). The primary science goal aims to achieve DFSZ sensitivity above $m_ac^2\approx 120$ neV (30 MHz), with a secondary science goal of probing KSVZ axions down to $m_ac^2\approx40\,\mathrm{neV}$ (10 MHz)., Comment: 8 pages, 4 figures. Updated to fix small errors and correct acknowledgements. Updated title and notational clarifications
- Published
- 2022
- Full Text
- View/download PDF
7. Proposal for a definitive search for GUT-scale QCD axions
- Author
-
Brouwer, L, Chaudhuri, S, Cho, H-M, Corbin, J, Dawson, CS, Droster, A, Foster, JW, Fry, JT, Graham, PW, Henning, R, Irwin, KD, Kadribasic, F, Kahn, Y, Keller, A, Kolevatov, R, Kuenstner, S, Leder, AF, Li, D, Ouellet, JL, Pappas, KMW, Phipps, A, Rapidis, NM, Safdi, BR, Salemi, CP, Simanovskaia, M, Singh, J, van Assendelft, EC, van Bibber, K, Wells, K, Winslow, L, Wisniewski, WJ, and Young, BA
- Subjects
Nuclear and Plasma Physics ,Particle and High Energy Physics ,Physical Sciences - Abstract
The QCD axion is a leading dark matter candidate that emerges as part of the solution to the strong CP problem in the Standard Model. The coupling of the axion to photons is the most common experimental probe, but much parameter space remains unexplored. The coupling of the QCD axion to the Standard Model scales linearly with the axion mass; therefore, the highly motivated region 0.4-120 neV, corresponding to a GUT-scale axion, is particularly difficult to reach. This paper presents the design requirements for a definitive search for GUT-scale axions and reviews the technological advances needed to enable this program.
- Published
- 2022
8. A Strategic Approach to Advance Magnet Technology for Next Generation Colliders
- Author
-
Ambrosio, G., Amm, K., Anerella, M., Apollinari, G., Arbelaez, D., Auchmann, B., Balachandran, S., Baldini, M., Ballarino, A., Barua, S., Barzi, E., Baskys, A., Bird, C., Boerme, J., Bosque, E., Brouwer, L., Caspi, S., Cheggour, N., Chlachidze, G., Cooley, L., Davis, D., Dietderich, D., DiMarco, J., English, L., Fajardo, L. Garcia, Fernandez, J. L. Rudeiros, Ferracin, P., Gourlay, S., Gupta, R., Hafalia, A., Hellstrom, E., Higley, H., Hossain, I., Jewell, M., Jiang, J., Juchno, GM., Kametani, F., Kashikhin, V., Krave, S., Kumar, M., Kurian, F., Lankford, A., Larbalestier, D., Lee, P., Lee, G. S., Lombardo, V., Marchevsky, M., Marinozzi, V., Messe, C., Minervini, J., Myers, C., Naus, M., Novitski, I., Ogitsu, T., Palmer, M., Pong, I., Prestemon, S., Runyan, C., Sabbi, G. L., Shen, T., Stoynev, S., Strauss, T., Tarantini, C., Teyber, R., Trociewitz, U., Turqueti, M., Turenne, M., Turrioni, D., Vallone, G., Velev, G., Viarengo, S., Wang, L., Wang, X., Xu, X., Yamamoto, A., Yin, S., and Zlobin, A.
- Subjects
Physics - Accelerator Physics - Abstract
Colliders are built on a foundation of superconducting magnet technology that provides strong dipole magnets to maintain the beam orbit and strong focusing magnets to enable the extraordinary luminosity required to probe physics at the energy frontier. The dipole magnet strength plays a critical role in dictating the energy reach of a collider, and the superconducting magnets are arguably the dominant cost driver for future collider facilities. As the community considers opportunities to explore new energy frontiers, the importance of advanced magnet technology - both in terms of magnet performance and in the magnet technology's potential for cost reduction - is evident, as the technology status is essential for informed decisions on targets for physics reach and facility feasibility., Comment: contribution to Snowmass 2021
- Published
- 2022
9. Introducing DMRadio-GUT, a search for GUT-scale QCD axions
- Author
-
Brouwer, L., Chaudhuri, S., Cho, H. -M., Corbin, J., Dawson, C. S., Droster, A., Foster, J. W., Fry, J. T., Graham, P. W., Henning, R., Irwin, K. D., Kadribasic, F., Kahn, Y., Keller, A., Kolevatov, R., Kuenstner, S., Leder, A. F., Li, D., Ouellet, J. L., Pappas, K. M. W., Phipps, A., Rapidis, N. M., Safdi, B. R., Salemi, C. P., Simanovskaia, M., Singh, J., van Assendelft, E. C., van Bibber, K., Wells, K., Winslow, L., Wisniewski, W. J., and Young, B. A.
- Subjects
High Energy Physics - Experiment ,High Energy Physics - Phenomenology - Abstract
The QCD axion is a leading dark matter candidate that emerges as part of the solution to the strong CP problem in the Standard Model. The coupling of the axion to photons is the most common experimental probe, but much parameter space remains unexplored. The coupling of the QCD axion to the Standard Model scales linearly with the axion mass; therefore, the highly-motivated region 0.4-120 neV, corresponding to a GUT-scale axion, is particularly difficult to reach. This paper presents the design requirements for a definitive search for GUT-scale axions and reviews the technological advances needed to enable this program., Comment: 16 pages, 4 figures
- Published
- 2022
- Full Text
- View/download PDF
10. Snowmass21 Accelerator Modeling Community White Paper
- Author
-
Biedron, S., Brouwer, L., Bruhwiler, D. L., Cook, N. M., Edelen, A. L., Filippetto, D., Huang, C. -K., Huebl, A., Katsouleas, T., Kuklev, N., Lehe, R., Lund, S., Messe, C., Mori, W., Ng, C. -K., Perez, D., Piot, P., Qiang, J., Roussel, R., Sagan, D., Sahai, A., Scheinker, A., Thévenet, M., Tsung, F., Vay, J. -L., Winklehner, D., and Zhang, H.
- Subjects
Physics - Accelerator Physics - Abstract
After a summary of relevant comments and recommendations from various reports over the last ten years, this paper examines the modeling needs in accelerator physics, from the modeling of single beams and individual accelerator elements, to the realization of virtual twins that replicate all the complexity to model a particle accelerator complex as accurately as possible. We then discuss cutting-edge and emerging computing opportunities, such as advanced algorithms, AI/ML and quantum computing, computational needs in hardware, software performance, portability and scalability, and needs for scalable I/O and in-situ analysis. Considerations of reliability, long-term sustainability, user support and training are considered next, before discussing the benefits of ecosystems with integrated workflows based on standardized input and output, and with integrated frameworks and data repositories developed as a community. Last, we highlight how the community can work more collaboratively and efficiently through the development of consortia and centers, and via collaboration with industry., Comment: contribution to Snowmass 2021
- Published
- 2022
11. Towards 20 T Hybrid Accelerator Dipole Magnets
- Author
-
Ferracin, P, Ambrosio, G, Arbelaez, D, Brouwer, L, Barzi, E, Cooley, L, Fajardo, L Garcia, Gupta, R, Juchno, M, Kashikhin, V, Marinozzi, V, Novitski, I, Rochepault, E, Stern, J, Zlobin, A, and Zucchi, N
- Subjects
Engineering ,Electrical Engineering ,Physical Sciences ,Dipole magnets ,hybrid magnets ,HTS ,Nb3Sn magnets ,superconducting ,Condensed Matter Physics ,Electrical and Electronic Engineering ,Materials Engineering ,General Physics ,Electrical engineering ,Condensed matter physics - Abstract
The most effective way to achieve very high collision energies in a circular particle accelerator is to maximize the field strength of the main bending dipoles. In dipole magnets using Nb-Ti superconductor the practical field limit is considered to be 8-9 T. When Nb3Sn superconductor material is utilized, a field level of 15-16 T can be achieved. To further push the magnetic field beyond the Nb3Sn limits, High Temperature Superconductors (HTS) need to be considered in the magnet design. The most promising HTS materials for particle accelerator magnets are Bi2212 and REBCO. However, their outstanding performance comes with a significantly higher cost. Therefore, an economically viable option towards 20 T dipole magnets could consist in an 'hybrid' solution, where both HTS and Nb3Sn materials are used. We discuss in this paper preliminary conceptual designs of various 20 T hybrid magnet concepts. After the definition of the overall design criteria, the coil dimensions and parameters are investigated with finite element models based on simple sector coils. Preliminary 2D cross-section computation results are then presented and three main layouts compared: cos-theta, block, and common-coil. Both traditional designs and more advanced stress-management options are considered.
- Published
- 2022
12. A Carbon-Ion Superconducting Gantry and a Synchrotron Based on Canted Cosine Theta Magnets
- Author
-
Benedetto, E., Harbi, N. Al, Brouwer, L., Tommasini, D., Prestemon, S., Riboni, P., and Amaldi, U.
- Subjects
Physics - Medical Physics ,Physics - Accelerator Physics - Abstract
This article presents the conceptual design of a new compact superconducting gantry and synchrotron for Carbon ion therapy and focuses on the solutions (layout and optics) to make it compact. The main specificity of this gantry design is to be smaller and lighter with respect to the existing carbon-ion gantries. This is achieved by adopting an innovative mechanical design and by using superconducting magnets of the Canted Cosine Theta type with a small aperture. The optics is optimized to reduce the beam size, it is achromatic and it is independent of the rotation angle (for an incoming round beam). A preliminary synchrotron layout based on similar superconducting magnets units is presented and the dose delivery specificities are discussed., Comment: Submitted to Physics in Medicine and Biology
- Published
- 2021
13. 3D Toroidal Field Multipoles for Curved Accelerator Magnets
- Author
-
Brouwer, L, Caspi, S, Robin, D, and Wan, W
- Published
- 2021
14. Inverse Biot-Savart Optimization for Superconducting Accelerator Magnets
- Author
-
Teyber, R, Brouwer, L, Qiang, J, and Prestemon, S
- Subjects
Biot-Savart ,inverse design ,particle accelerator ,quadratic programming ,superconducting (SC) magnet ,topology optimization ,Applied Physics ,Physical Sciences ,Engineering - Abstract
Superconducting (SC) magnets for accelerator concepts are often synthesized by numerically optimizing magnetic field waveforms, a process that requires a subsequent solution of a constrained inverse problem to identify suitable SC magnet windings. When the desired field distribution is intuitive, the inverse process is facilitated by seeding preconceived coil distributions into design optimization methods for refinement. With more complex magnetic field distributions, an initial design may be unknown, and topology optimization tools are required to synthesize current distributions without a priori guidance from a subject matter expert. In this work, we develop a constrained inverse Biot-Savart topology optimization methodology that synthesizes optimal distributions of current density in racetrack-like SC coils. The problem structure is exploited through a computationally efficient quadratic programming formulation, and the method is applied to recently published magnetic field waveforms for a recirculating proton phase shifter, a proton therapy gantry, and dipole magnets with sharp field transitions. The method and results herein identify novel winding configurations that can help magnet designers bring accelerator concepts to fruition.
- Published
- 2021
15. Modeling Training in Nb3Sn Superconducting Magnets
- Author
-
Vallone, G., primary, Anderssen, E., additional, Arbelaez, D., additional, Brouwer, L., additional, Ferracin, P., additional, Fernandez, JL Rudeiros, additional, Shen, T., additional, and Teyber, R., additional
- Published
- 2024
- Full Text
- View/download PDF
16. Fixed field phase shifters for a multipass recirculating superconducting proton linac
- Author
-
Qiang, J, Brouwer, L, and Teyber, R
- Abstract
The multi-pass recirculating proton linac can significantly improve the usage efficiency of rf superconducting cavities by accelerating the proton beam through the same cavity multiple times. However, in order to achieve acceleration for different energy proton beams, longitudinal phase synchronous conditions among these beams have to be satisfied. In this paper, we propose a fixed field phase shifter system based on two superconducting bending magnets with an optimized field distribution to meet the synchronous conditions. Such a phase shifter provides both longitudinal phase delay and transverse focusing of multiple energy beams. Self-consistent macroparticle simulations including space-charge effects through the system show that the proton beam emittances can be well preserved after the phase shifter for multiple energy beams.
- Published
- 2021
17. Development and performance of a 2.9 Tesla dipole magnet using high-temperature superconducting CORC®wires
- Author
-
Wang, X, Abraimov, D, Arbelaez, D, Bogdanof, TJ, Brouwer, L, Caspi, S, DIetderich, DR, DImarco, J, Francis, A, Garcia Fajardo, L, Ghiorso, WB, Gourlay, SA, Higley, HC, Marchevsky, M, Maruszewski, MA, Myers, CS, Prestemon, SO, Shen, T, Taylor, J, Teyber, R, Turqueti, M, Van Der Laan, D, and Weiss, JD
- Subjects
REBCO ,dipole accelerator magnet ,CORC® ,Condensed Matter Physics ,Electrical and Electronic Engineering ,Materials Engineering ,General Physics - Abstract
Although the high-temperature superconducting (HTS) REBa2Cu3O x (REBCO, RE-rare earth elements) material has a strong potential to enable dipole magnetic fields above 20 T in future circular particle colliders, the magnet and conductor technology needs to be developed. As part of an ongoing development to address this need, here we report on our CORC® canted cosθ magnet called C2 with a target dipole field of 3 T in a 65 mm aperture. The magnet was wound with 70 m of 3.8 mm diameter CORC® wire on machined metal mandrels. The wire had 30 commercial REBCO tapes from SuperPower Inc. each 2 mm wide with a 30 µm thick substrate. The magnet generated a peak dipole field of 2.91 T at 6.290 kA, 4.2 K. The magnet could be consistently driven into the flux-flow regime with reproducible voltage rise at an engineering current density between 400-550 A mm-2, allowing reliable quench detection and magnet protection. The C2 magnet represents another successful step towards the development of high-field accelerator magnet and CORC® conductor technologies. The test results highlighted two development needs: continue improving the performance and flexibility of CORC® wires and develop the capability to identify locations of first onset of flux-flow voltage.
- Published
- 2021
18. Thermoeconomic cost optimization of superconducting magnets for proton therapy gantries
- Author
-
Teyber, R, Brouwer, L, Godeke, A, and Prestemon, S
- Subjects
proton therapy ,superconducting magnet ,thermoeconomics ,cryocooler ,REBCO ,BSCCO ,Nb3Sn ,General Physics ,Condensed Matter Physics ,Electrical and Electronic Engineering ,Materials Engineering - Abstract
A compact gantry delivering 70-220 MeV protons with fixed field in the superconducting magnets could reduce the cost and improve the adoption of proton therapy. While a number of magnet and cryogenics designs have been proposed, the combined capital and operating costs of state-of-the-art superconducting materials have not been analyzed. In response, we develop a thermoeconomic model of a multi-stage, conduction cooled gantry lattice and analyze the cryocooler operating cost, cryocooler capital cost and conductor capital cost for Nb-Ti, Nb3Sn, REBCO and Bi-2223 over a continuous range of magnet temperatures, and a differential evolution algorithm is used to identify the optimal combination of thermal intercept temperatures. Although Nb3Sn yields the lowest Net Present Value (NPV) of $111.7k at a magnet temperature of 9.4 K, the optimized Bi-2223 design at 12.8 K approaches the realm of commercial feasibility by offering improved thermal stability and forgoing the need for costly conductor heat treatment and magnet quench training. Furthermore, it was found that Nb3Sn was more cost effective than Nb-Ti and that REBCO was not economically viable for the parameters of this investigation. The thermoeconomic model developed herein can optimize conductor choices, magnet temperatures and thermal staging which has value for any conduction-cooled superconducting magnet.
- Published
- 2020
19. A country‐wide examination of effects of urbanization on common birds
- Author
-
Brouwer, L., primary, de Vries, E.H.J., additional, Sierdsema, H., additional, and van der Jeugd, H.P., additional
- Published
- 2024
- Full Text
- View/download PDF
20. User defined elements in ANSYS for 2D multiphysics modeling of superconducting magnets
- Author
-
Brouwer, L, Arbelaez, D, Auchmann, B, Bortot, L, and Stubberud, E
- Subjects
superconducting magnets ,multiphysics modeling ,finite element ,quench protection ,superconducting undulators ,Condensed Matter Physics ,Materials Engineering ,Electrical and Electronic Engineering ,General Physics - Abstract
Dynamic simulation of superconducting magnets is critical for the design of quench protection systems to prevent potentially damaging temperatures and high voltage from developing after magnet quench. Modeling these scenarios is challenging due to the many multiscale phenomena which impact magnet behavior. These range from conductor scale effects of quench and interfilament coupling currents up to the behavior of the magnet in its powering and protection circuit. In addition, a strong coupling between electromagnetic and thermal domains is required to capture temperature and field dependent material properties and quench behavior. We present a finite element approach which integrates the various effects into the commercial software ANSYS by means of programming new element types. This is shown capable of simulating the strongly coupled transient electromagnetic, thermal, and circuit behavior of superconducting magnets required for quench protection studies. A benchmarking study is presented which shows close agreement between the new ANSYS elements and a COMSOL Multiphysics implementation developed at CERN for dump resistor and coupling loss induced quench based magnet protection of a Nb3Sn block dipole. Following this, the ANSYS implementation is shown reproducing strongly coupled quench back behavior observed during the test of a Nb3Sn superconducting undulator prototype at Lawrence Berkeley National Laboratory.
- Published
- 2019
21. Mechanical utility structure for testing high field superconducting dipole magnets
- Author
-
Juchno, M, Brouwer, L, Caspi, S, Hafalia, A, Novitski, I, Prestemon, S, and Zlobin, A
- Subjects
Dipole magnet ,finite element analysis ,Nb3Sn ,support structure ,Bioengineering ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering ,General Physics - Abstract
The U.S. Magnet Development Program (MDP) collaboration is designing a utility mechanical structure for testing various high-field superconducting dipole coils. The design uses a shell-based structure concept, which allows applying preload in two steps: During a room temperature assembly and during a cool down to a cryogenic temperature. The structure is designed to accommodate various coil designs - including Nb3Sn Cosine Theta (CT) and Canted CT magnets as well as hybrid magnets with high temperature superconductor cables. Superconducting coils, enclosed by bolted pads to form an octagonal coil pack, will be inserted into a reusable yoke-shell subassembly and precisely preloaded during the assembly using a bladder-and-key technology. Due to a differential thermal contraction between an external aluminum shell and the magnet core, the coil preload increases during the cool down up to level required for 17-T excitation. Such a reusable structure will serve as a testing fixture supporting goals of the MDP program, decreasing cost and simplifying coil performance testing at different preload levels. We present a finite-element analysis of the structure preloading various coil designs and examine the predicted coil stress at each step of the magnet assembly and excitation.
- Published
- 2019
22. Fabrication of Bi-2212 Canted-Cosine-Theta Dipole Prototypes
- Author
-
Fajardo, LG, Brouwer, L, Caspi, S, Hafalia, A, Hernikl, C, Prestemon, S, Shen, T, Bosque, E, and English, C
- Subjects
Bi-2212 coil fabrication ,canted cosine theta magnets ,HTS insert magnets ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering ,General Physics - Abstract
The U.S. Magnet Development Program (MDP) is exploring the possibility of combining low-and higherature superconductor technologies, using cosine-theta and canted-cosine-theta (CCT) Nb3Sn dipole magnets together with Bi-2212 CCT inserts, with the ultimate goal of constructing a 20-T dipole. The MDP short-term goal is a Bi-2212 CCT insert capable of reaching 5 T in the bore when operating as a stand-alone and 3 T when operating under a background field of 15 T. This paper reports on the fabrication of our BIN4 dipole magnet and our BIN5a and BIN5b coils, designed and built at the Lawrence Berkeley National Laboratory to address potential fabrication issues of Bi-2212 coils and verify the design of our 18-20-T dipole magnet. BIN4 is a two-layer 50-cm-long CCT magnet that uses a nine-strand Rutherford cable made with 0.8-mm-diameter Bi-2212 strands. Its goal is to investigate critical current, insulation integrity, manufacturing challenges, and quench protection issues after heat treating both layers together under oxygen at standard atmosphere (1 bar). BIN5a and BIN5b are two identical coils, similar to the outer layer of BIN4, with the difference that the length is 39 cm, and they will undergo 50-bar overpressure processing heat treatment. BIN5 coils are made from the state-of-the-art strand with an engineering critical current density of 1150 A/mm2 at 4.2 K and 5 T.
- Published
- 2019
23. The 16 T Dipole Development Program for FCC and HE-LHC
- Author
-
Schoerling, D, Arbelaez, D, Auchmann, B, Bajko, M, Ballarino, A, Barzi, E, Bellomo, G, Benedikt, M, Bermudez, SI, Bordini, B, Bottura, L, Brouwer, L, Bruzzone, P, Caiffi, B, Caspi, S, Chakraborti, A, Coatanea, E, De Rijk, G, Dhalle, M, Durante, M, Fabbricatore, P, Farinon, S, Felice, H, Fernandez, A, Fernandez, IS, Gao, P, Gold, B, Gortsas, T, Gourlay, S, Juchno, M, Kashikhin, V, Kokkinos, C, Kokkinos, S, Koskinen, K, Lackner, F, Lorin, C, Loukas, K, Louzguiti, A, Lyytikainen, K, Mariotto, S, Marchevsky, M, Montenero, G, Munilla, J, Novitski, I, Ogitsu, T, Pampaloni, A, Perez, JC, Pes, C, Petrone, C, Polyzos, D, Prestemon, S, Prioli, M, Ricci, AM, Rifflet, JM, Rochepault, E, Russenschuck, S, Salmi, T, Santillana, IA, Savary, F, Scheuerlein, C, Segreti, M, Senatore, C, Sorbi, M, Statera, M, Stenvall, A, Tavian, L, Tervoort, T, Tommasini, D, Toral, F, Valente, R, Velev, G, Verweij, AP, Wessel, S, Wolf, F, Zimmermann, F, and Zlobin, AV
- Subjects
FCC ,Nb3Sn ,superconducting ,T ,General Physics ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering - Abstract
A future circular collider (FCC) with a center-of-mass energy of 100 TeV and a circumference of around 100 km, or an energy upgrade of the LHC (HE-LHC) to 27 TeV require bending magnets providing 16 T in a 50-mm aperture. Several development programs for these magnets, based on Nb3Sn technology, are being pursued in Europe and in the U.S. In these programs, cos-theta, block-type, common-coil, and canted-cos-theta magnets are explored; first model magnets are under manufacture; limits on conductor stress levels are studied; and a conductor with enhanced characteristics is developed. This paper summarizes and discusses the status, plans, and preliminary results of these programs.
- Published
- 2019
24. Designs and Prospects of Bi-2212 Canted-Cosine-Theta Magnets to Increase the Magnetic Field of Accelerator Dipoles beyond 15 T
- Author
-
Garcia Fajardo, L, Brouwer, L, Caspi, S, Gourlay, S, Prestemon, S, and Shen, T
- Subjects
Bi-2212 dipole ,canted cosine theta ,HTS insert magnets ,General Physics ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering - Abstract
The critical current density of Bi-2212 round wires has seen significant improvement over the past two years. We present the magnetic design and stress analysis of two Bi-2212 dipoles based on Canted-Cosine-Theta (CCT) technology using the state-of-the-art wires. The first design, based on a 19-strand Rutherford cable of θ0.8mm strands, is a two-layer dipole with a bore diameter of 40 mm and an outer diameter of 98.4 mm; it generates 5.4Twhen operating in stand-alone configuration and 18.9T in 15 T background field. The second design, based on a 13-strand Rutherford cable of θ0.8mm strands, is also a two-layer dipole with a bore diameter of 40 mm and an outer diameter of 81 mm; it generates 4.0 T when operating in stand-alone configuration and 17.8 T in 15 T background field. Normal stresses on the conductor in these magnets do not exceed 35 MPa when working under background field.Moreover, we propose a novel approach for increasing the efficiency of CCT magnets using keystoned Rutherford cable while removing the midplane ribs. with this method, it is possible to increase the efficiency of small radius CCT coils by 20%. We conclude that Bi-2212 can be used to increase the limit of accelerator magnet dipole fields beyond 15 T while managing stresses in the coils to acceptable levels.
- Published
- 2018
25. Electromechanical design of a 16-T CCT twin-aperture dipole for FCC
- Author
-
Auchmann, B, Brouwer, L, Caspi, S, Gao, J, Montenero, G, Negrazus, M, Rolando, G, and Sanfilippo, S
- Subjects
FCC ,CCT ,Nb3Sn accelerator magnet ,General Physics ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering - Abstract
© 2017 EU. Canted-cosine-theta (CCT) technology has been studied for its suitability for a future-circular-collider (FCC) main dipole in terms of magnetic and mechanical performance, elec-trothermal protectability, as well as efficiency. In this paper, we present lessons learnt from our search for efficient CCT solutions by means of two-dimensional (2-D) magnetic and mechanical simulations, discuss the 3-D periodic mechanical model, as well as 3-D electromagnetic analysis of the end regions. Temperature and voltage distributions during a quench under simplifying assumptions are discussed, and the magnet’s efficiency is compared to that of other contenders in the FCC design study. The results qualify the CCT design as a contender for the FCC main dipole.
- Published
- 2018
26. Improved modeling of canted–cosine–theta magnets
- Author
-
Brouwer, L, Arbelaez, D, Caspi, S, Marchevsky, M, and Prestemon, S
- Subjects
Accelerator magnets ,canted-cosine-theta ,high field ,superconducting dipole ,advanced modeling ,General Physics ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering - Abstract
The Canted–Cosine–Theta is a design option for the next generation of high field superconducting dipoles being pursued within the US Magnet Development Program. This paper presents new modeling techniques developed for design and analysis of CCT magnets. For mechanical modeling in ANSYS, three approaches with increasing accuracy are compared: 2-D symmetry models; 3-D periodic symmetry models; and full 3-D models. Methods for the static and transient magnetic simulation using ANSYS are presented with a focus on circuit-coupled models for predicting magnet behavior following quench. Where applicable, simulation results are compared to data from CCT magnet tests at Berkeley.
- Published
- 2018
27. Mechanical Structure for the PSI Canted-Cosine-Theta (CCT) Magnet Program
- Author
-
Montenero, G, Auchmann, B, Brouwer, L, Calzolaio, C, Caspi, S, Rolando, G, and Sanfilippo, S
- Subjects
Superconducting magnets ,accelerator magnets ,magnet structure ,Bioengineering ,General Physics ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering - Abstract
The Canted-Cosine-Theta (CCT) technology has the potential, by its intrinsic stress-management, to lower coil stresses in high-field accelerator magnets. This is especially relevant for Nb3Sn magnets, which may be subject to irreversible degradation if the coil stresses exceed critical values. The internal structure of CCT coils, however, dilutes the engineering current density. For an efficient design, the internal structure, therefore, needs to be reduced to the limit given by the computer-numerical-control machining capabilities. In that case, however, additional mechanical stiffness must be provided by an external mechanical structure. The mechanical structure for the Paul Scherrer Institut (PSI) CCT program, which is described in this paper, is based on the bladder and key concept. The CCT-specific deviations from the prevalent bladder and key implementations are discussed. In addition, a two-dimensional and three-dimensional analysis in all stages of loading, cooling, and powering of the first PSI magnet prototype, as well as a tolerance analysis, is reported.
- Published
- 2018
28. Design of an Achromatic Superconducting Magnet for a Proton Therapy Gantry
- Author
-
Brouwer, L, Caspi, S, Hafalia, R, Hodgkinson, A, Prestemon, S, Robin, D, and Wan, W
- Subjects
Accelerator magnets ,superconducting gantry magnets ,proton therapy ,ion beam therapy ,canted-cosine-theta ,General Physics ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering - Abstract
Recent studies have shown that strong, alternating focusing magnets can be used to greatly increase the momentum acceptance of hadron therapy gantries. With the high gradients achievable with superconducting magnets a level of momentum acceptance can be reached which may have significant implications to medical gantries and to the introduction of superconducting technology in this area. The design of such a superconducting magnet system for a proton therapy gantry will be presented. The Canted-Cosine-Theta concept is extended to a curved magnet system generating the desired bending and alternating focusing fields for the achromatic optics. Magnetic, structural, and thermal analysis of this design is presented along with preliminary efforts towards fabrication and assembly of the curved magnet.
- Published
- 2017
29. Design of a canted-cosine-theta superconducting dipole magnet for future colliders
- Author
-
Caspi, S, Arbelaez, D, Brouwer, L, Gourlay, S, Prestemon, S, and Auchmann, B
- Subjects
CCT ,Canted-Cosine-Theta ,superconducting ,magnet ,high field ,dipole ,16T ,2-in-1 ,General Physics ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering - Abstract
A four-layer canted-cosine-theta 16-T dipole has been designed as a possible candidate for future hadron colliders. The design maintains part of the future-circular-collider magnet requirements, i.e., a 50 mm clear bore and 16 T operating at 1.9 K. The magnet intercepts Lorentz forces with an internal structure of ribs and spars, minimizes conductor, and reduces the number of layers and magnet size by using wide cables. The role of iron and its impact on field and magnet size is discussed. A three-dimensional magnetic analysis was carried out for 1-in-1 and 2-in-1 designs including a structural analysis for the 1-in-1 case. Thoughts on future improvements during winding are also discussed.
- Published
- 2017
30. Modeling Training in Nb3Sn Superconducting Magnets
- Author
-
Vallone, G., Anderssen, E., Arbelaez, D., Brouwer, L., Ferracin, P., Fernandez, JL Rudeiros, Shen, T., and Teyber, R.
- Abstract
Stress managed magnet designs allow to limit the strain and stresses applied to the conductor during assembly and operation. In canted cos(
) (CCT) designs, the conductor is wound around a mandrel: the impregnation process creates a bonding between the two, that can fail during magnet powering. The energy releases due to debonding are considered a potential cause of training quenches. In this study, we investigate these events modeling the mandrel-conductor interfaces by means of cohesive zone material models. The material properties were calibrated by means of measurements performed on representative interfaces, and the models were validated comparing the results with strain gauge measurements. A thermal model was used to compute the local temperature increase in the strands as a function of the energy released by debonding and frictional sliding across the newly formed interfaces. The result was then used to define a quench condition for the model, allowing to simulate the full training process of the CCT magnet. The obtained training curve is in reasonable agreement with the experimental results.$\theta$ - Published
- 2024
- Full Text
- View/download PDF
31. Design and test of a curved superconducting dipole magnet for proton therapy
- Author
-
Brouwer, L., Caspi, S., Edwards, K., Godeke, A., Hafalia, R., Hodgkinson, A., Huggins, A., Myers, C., Myers, S., Schillo, M., Taylor, J., Turqueti, M., Wang, X., Wan, W., and Prestemon, S.
- Published
- 2020
- Full Text
- View/download PDF
32. On the mechanical behavior of a Nb3Sn superconducting coil during a quench: Two-dimensional finite element analysis of a quench heater protected magnet
- Author
-
Troitino, J. Ferradas, Ambrosio, G., Bajas, H., Brouwer, L., Ferracin, P., Bermudez, S. Izquierdo, Gomez, J.V. Lorenzo, Mangiarotti, F.J., Perez, J.C., Ravaioli, E., Taakala, E. Tapani, Vallone, G., and Senatore, C.
- Published
- 2020
- Full Text
- View/download PDF
33. Alternating-gradient canted cosine theta superconducting magnets for future compact proton gantries
- Author
-
Wan, W, Brouwer, L, Caspi, S, Prestemon, S, Gerbershagen, A, Schippers, JM, and Robin, D
- Subjects
Nuclear & Particles Physics ,Physical Sciences - Abstract
We present a design of superconducting magnets, optimized for application in a gantry for proton therapy. We have introduced a new magnet design concept, called an alternating-gradient canted cosine theta (AG-CCT) concept, which is compatible with an achromatic layout. This layout allows a large momentum acceptance. The 15 cm radius of the bore aperture enables the application of pencil beam scanning in front of the SC-magnet. The optical and dynamic performance of a gantry based on these magnets has been analyzed using the fields derived (via Biot-Savart law) from the actual windings of the AG-CCT combined with the full equations of motion. The results show that with appropriate higher order correction, a large 3D volume can be rapidly scanned with little beam shape distortion. A very big advantage is that all this can be done while keeping the AG-CCT fields fixed. This reduces the need for fast field ramping of the superconducting magnets between the successive beam energies used for the scanning in depth and it is important for medical application since this reduces the technical risk (e.g., a quench) associated with fast field changes in superconducting magnets. For proton gantries the corresponding superconducting magnet system holds promise of dramatic reduction in weight. For heavier ion gantries there may furthermore be a significant reduction in size.
- Published
- 2015
34. Design of an 18-T Canted Cosine–Theta Superconducting Dipole Magnet
- Author
-
Caspi, S, Brouwer, L, Lipton, T, Hafalia, A, Prestemon, S, Dietderich, D, Felice, H, Wang, X, Rochepault, E, Godeke, A, Gourlay, S, and Marchevsky, M
- Subjects
Canted cosine-theta ,dipole ,high field ,magnet ,superconducting ,Condensed Matter Physics ,Electrical and Electronic Engineering ,Materials Engineering ,General Physics - Abstract
A multilayer high field dipole magnet has been designed for future particle accelerators. The magnet has eight layers of a Nb3Sn outsert coil and four layers of a Bi-2212 insert coil (see Figs. 1 and 2). The layers are graded, delivering a short-sample field of 17.7 T in a 40-mm bore. The coil layers are of a canted cosine-theta design - with ribs and spars that guide and support the coil windings, shape the field, intercept Lorentz forces, and minimize conductor prestress. We present a general overview of the concept and report on the magnetic and mechanical design including an initial cost estimate and construction plan.
- Published
- 2015
35. Canted–Cosine–Theta Magnet (CCT)—A Concept for High Field Accelerator Magnets
- Author
-
Caspi, S, Borgnolutti, F, Brouwer, L, Cheng, D, Dietderich, DR, Felice, H, Godeke, A, Hafalia, R, Martchevskii, M, Prestemon, S, Rochepault, E, Swenson, C, and Wang, X
- Subjects
Engineering ,Electrical Engineering ,Affordable and Clean Energy ,Accelerator magnets ,Canted-Cosine-Theta magnet ,CCT ,high field ,superconducting dipole ,Condensed Matter Physics ,Electrical and Electronic Engineering ,Materials Engineering ,General Physics ,Electrical engineering ,Condensed matter physics - Abstract
Canted-Cosine-Theta (CCT) magnet is an accelerator magnet that superposes fields of nested and tilted solenoids that are oppositely canted. The current distribution of any canted layer generates a pure harmonic field as well as a solenoid field that can be cancelled with a similar but oppositely canted layer. The concept places windings within mandrel's ribs and spars that simultaneously intercept and guide Lorentz forces of each turn to prevent stress accumulation. With respect to other designs, the need for pre-stress in this concept is reduced by an order of magnitude making it highly compatible with the use of strain sensitive superconductors such as Nb3Sn or HTS. Intercepting large Lorentz forces is of particular interest in magnets with large bores and high field accelerator magnets like the one foreseen in the future high energy upgrade of the LHC. This paper describes the CCT concept and reports on the construction of CCT1 a "proof of principle" dipole.
- Published
- 2014
36. Structural Design and Analysis of Canted–Cosine–Theta Dipoles
- Author
-
Brouwer, L, Arbelaez, D, Caspi, S, Felice, H, Prestemon, S, and Rochepault, E
- Subjects
Accelerator magnets ,canted-cosine-theta ,high field ,superconducting magnets ,Condensed Matter Physics ,Electrical and Electronic Engineering ,Materials Engineering ,General Physics - Abstract
The Canted-Cosine-Theta (CCT) magnet design offer significant reductions in conductor stress by using mandrels t prevent the accumulation of operating Lorentz forces. Each mandre consists of a cylindrical spar with ribs guiding the conductor These ribs intercept the turn-To-Turn accumulation of forces b transferring them to the spar. Design studies of a layered CC coil pack coupled to a shell-based structure are shown. The us of a 3-D periodic symmetry region to reduce the problem size fo finite element modeling is detailed along with a discussion of axia boundary conditions. ANSYS calculation results for a two laye NbTi dipole being constructed at LBNL (CCT1) are presented ANSYS calculations show the Lorentz force induced stress i CCT1 at the single turn level, demonstrating interception an suggesting investigation of CCT design with minimal structur external to the coil pack.
- Published
- 2014
37. The structural design for a "canted cosine-theta" Superconducting dipole coil and magnet structure-CCT
- Author
-
Hafalia, A, Caspi, S, Felice, H, Brouwer, L, Prestemon, S, and Godeke, A
- Subjects
Bladder & key ,canted cosine-theta ,dipole ,superconducting ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Materials Engineering ,General Physics - Abstract
The Superconducting Magnet Group, at Lawrence Berkeley National Laboratory (LBNL), has been developing a canted cosine-theta (CCT) superconducting dipole coil as well as the coil's supporting magnet structure. This contribution reports on the progress in the development of the coil's winding mandrel and its fabrication options. A comprehensive study of the coil's Lorentz forces was performed to validate the winding mandrel's "stress interception" attributes. The design of the external structure and the application of the "Bladder & Key" technology is also discussed. Additionally, the application of these studies to a curved ion-therapy CCT dipole magnet is reported.
- Published
- 2014
38. Conceptual Design of 20 T Hybrid Accelerator Dipole Magnets
- Author
-
Ferracin, P., primary, Ambrosio, G., additional, Anerella, M., additional, Arbelaez, D., additional, Brouwer, L., additional, Barzi, E., additional, Cooley, L. D., additional, Cozzolino, J., additional, Garcia Fajardo, L., additional, Gupta, R., additional, Juchno, M., additional, Kashikhin, V. V., additional, Kurian, F., additional, Marinozzi, V., additional, Novitski, I., additional, Rochepault, E., additional, Stern, J., additional, Vallone, G., additional, Yahia, B., additional, and Zlobin, A.V., additional
- Published
- 2023
- Full Text
- View/download PDF
39. Social context-dependent provisioning rules in red-winged fairy-wrens do not vary with signals of increased chick need
- Author
-
MacLeod, K.J. and Brouwer, L.
- Published
- 2018
- Full Text
- View/download PDF
40. A superconducting magnet mandrel with minimum symmetry laminations for proton therapy
- Author
-
Caspi, S, Arbelaez, D, Brouwer, L, Dietderich, DR, Felice, H, Hafalia, R, Prestemon, S, Robin, D, Sun, C, and Wan, W
- Subjects
Curved dipole magnet ,Superconducting ,Gantry ,Hadron therapy ,Canted cosine-theta ,Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Other Physical Sciences ,Nuclear & Particles Physics - Abstract
The size and weight of ion-beam cancer therapy gantries are frequently determined by a large aperture, curved, ninety degree, dipole magnet. The higher fields achievable with superconducting technology promise to greatly reduce the size and weight of this magnet and therefore also the gantry as a whole. This paper reports advances in the design of winding mandrels for curved, canted cosine-theta (CCT) magnets in the context of a preliminary magnet design for a proton gantry. The winding mandrel is integral to the CCT design and significantly affects the construction cost, stress management, winding feasibility, eddy current power losses, and field quality of the magnet. A laminated mandrel design using a minimum symmetry in the winding path is introduced and its feasibility demonstrated by a rapid prototype model. Piecewise construction of the mandrel using this laminated approach allows for increased manufacturing techniques and material choices. Sectioning the mandrel also reduces eddy currents produced during field changes accommodating the scan of beam energies during treatment. This symmetry concept can also greatly reduce the computational resources needed for 3D finite element calculations. It is shown that the small region of symmetry forming the laminations combined with periodic boundary conditions can model the entire magnet geometry disregarding the ends. © 2013 Elsevier B.V.
- Published
- 2013
41. Electromechanical analysis for the integration of a Nb3Sn and a Bi-2212 CCT dipole magnet for a hybrid magnet test
- Author
-
Fajardo, L.Garcia, primary, Shen, T., additional, Hafalia, A., additional, Arbelaez, D., additional, Brouwer, L., additional, Ferracin, P., additional, Prestemon, S., additional, and Fernandez, J.Rudeiros, additional
- Published
- 2023
- Full Text
- View/download PDF
42. Impact of high pressure and shear thinning on journal bearing friction
- Author
-
Sander, D.E., Allmaier, H., Priebsch, H.H., Reich, F.M., Witt, M., Füllenbach, T., Skiadas, A., Brouwer, L., and Schwarze, H.
- Published
- 2015
- Full Text
- View/download PDF
43. Projected sensitivity of <math><mrow><msup><mrow><mtext>DMRadio-m</mtext></mrow><mrow><mn>3</mn></mrow></msup></mrow></math>: A search for the QCD axion below <math><mrow><mn>1</mn><mtext> </mtext><mtext> </mtext><mi>μ</mi><mi>eV</mi></mrow></math>
- Author
-
Brouwer, L., Chaudhuri, S., Cho, H.M., Corbin, J., Craddock, W., Dawson, C. S., Droster, A., Foster, J. W., Fry, J. T., Graham, P. W., Henning, R., Irwin, K. D., Kadribasic, F., Kahn, Y., Keller, A., Kolevatov, R., Kuenstner, S., Leder, A. F., Li, D., Ouellet, J. L., Pappas, K. M. W., Phipps, A., Rapidis, N. M., Safdi, B. R., Salemi, C. P., Simanovskaia, M., Singh, J., van Assendelft, E. C., van Bibber, K., Wells, K., Winslow, L., Wisniewski, W. J., and Young, B. A.
- Abstract
The QCD axion is one of the most compelling candidates to explain the dark matter abundance of the Universe. With its extremely small mass (≪1 eV/c2), axion dark matter interacts as a classical field rather than a particle. Its coupling to photons leads to a modification of Maxwell’s equations that can be measured with extremely sensitive readout circuits. DMRadio-m3 is a next-generation search for axion dark matter below 1 μeV using a >4 T static magnetic field, a coaxial inductive pickup, a tunable LC resonator, and a DC-SQUID readout. It is designed to search for QCD axion dark matter over the range 20 neV≲mac2≲800 neV (5 MHz<ν<200 MHz). The primary science goal aims to achieve Dine-Fischler-Srednicki-Zhitnitsky sensitivity above mac2≈120 neV (30 MHz), with a secondary science goal of probing Kim-Shifman-Vainshtein-Zakharov axions down to mac2≈40 neV (10 MHz).
- Published
- 2022
44. Design and rationale of the ATtune Knee Outcome Study (ATKOS): multicenter prospective evaluation of a novel uncemented rotating platform knee system
- Author
-
Rassir, R., Sierevelt, I.N., Schager, M., Nolte, P.A., Rademakers, M.V., Vergroesen, D.A., Spruijt, P., Baas, N.R.A., Sonnega, R.J.A., van Kampen, P.M., Lacroix, H., Verra, W.C., van Lingen, C.P., Boymans, T.A.E.J., Feczko, P.Z., Jutten-Brouwer, L., Jansen, J.A., Henkus, H.E., Benard, M.R., Meermans, G., MUMC+: MA Orthopedie (9), Onderwijsontw & Onderwijsresearch, RS: SHE - R1 - Research (OvO), Orthopedie, and RS: CAPHRI - R3 - Functioning, Participating and Rehabilitation
- Subjects
Work ,CEMENTLESS FIXATION ,Sports medicine ,Knee Joint ,medicine.medical_treatment ,Osteoarthritis ,Survivorship ,Diseases of the musculoskeletal system ,Attune ,Study Protocol ,0302 clinical medicine ,BROKEN DREAMS ,Outcome Assessment, Health Care ,Orthopedics and Sports Medicine ,Prospective Studies ,Arthroplasty, Replacement, Knee ,Pain catastrophizing ,Sport ,030222 orthopedics ,PATIENT SATISFACTION ,Rehabilitation ,PAIN ,Pain self-efficacy ,Osteoarthritis, Knee ,Treatment Outcome ,ARTHROPLASTY MINIMUM ,Patient-reported outcome ,Knee Prosthesis ,medicine.medical_specialty ,Joint replacement ,DUTCH VERSION ,03 medical and health sciences ,Rheumatology ,TOTAL HIP ,Uncemented ,medicine ,Humans ,SELF-EFFICACY QUESTIONNAIRE ,business.industry ,030229 sport sciences ,medicine.disease ,Patient reported outcome measures ,FORGOTTEN JOINT ,RC925-935 ,Total knee arthroplasty ,Orthopedic surgery ,Physical therapy ,Observational study ,business ,FOLLOW-UP - Abstract
BackgroundTotal Knee Arthroplasty (TKA) remains the gold standard for treatment of debilitating symptoms of knee osteoarthritis (OA). Even though providing satisfactory results for the majority of patients, some studies report dissatisfaction after TKA to be as high as 20%. Among other things, pain catastrophising and self-efficacy are thought to compromise results of TKA. Implant manufacturers keep improving upon their designs in an attempt to improve functional outcomes. One of these novel knee systems is the Attune. To our knowledge, there are no clinical follow-up studies reporting results of the uncemented version. The main objective of this multicentre prospective observational study is to evaluate revision rate, complications, radiographic outcomes (i.e. alignment and radiolucent lines) and patient reported outcomes of the uncemented Attune mobile bearing TKA. Secondary objectives are (1) to assess physical function, return to sport and return to work after TKA and (2) to evaluate the long-term effect of preoperative psychological factors on satisfaction after TKA.MethodsAll patients presenting in the participating centres with knee pathology warranting joint replacement therapy will be considered for inclusion, an absolute indication for cemented fixation is the only exclusion criterium. Evaluation of clinical and radiographic performance (e.g. radiolucent lines) is done at 6 weeks, 6 months, 1 year, 5 years and 10 years after surgery using validated patient reported outcome measures. Cumulative revision rates are calculated after 5 and 10 years using Kaplan–Meier methods. Physical function is assessed with performance based measurements before and 1 year after surgery. Return to sports is assessed using the Tegner and University of California Los Angeles (UCLA) activity rating scale before and 1 year after surgery. Return to work is evaluated by inviting patients of working age to complete a short questionnaire 1 year after surgery. Psychologic factors are assessed using questionnaires for pain catastrophising, pain self-efficacy and mental health before, 5 years and 10 years after surgery. Preoperative psychologic scores are correlated to functional outcomes.DiscussionThe current study aims to report the clinical performance of a novel implant and can help provide insight in factors that play a role in satisfaction after TKA.Trial registrationClinicalTrials.gov identifier: NCT04247672 (January 30, 2020)
- Published
- 2021
45. Assembly and Mechanical Analysis of the Canted-Cosine-Theta Subscale Magnets
- Author
-
Fernandez, J. L. Rudeiros, primary, Arbelaez, D., additional, Brouwer, L., additional, Caspi, S., additional, Ferracin, P., additional, Hafalia, R., additional, Krutulis, M., additional, Prestemon, S., additional, Reynolds, M., additional, Shen, T., additional, Swanson, J., additional, and Vallone, G., additional
- Published
- 2022
- Full Text
- View/download PDF
46. Design of CCT6: A Large Aperture, Nb$_3$Sn Dipole Magnet for HTS Insert Testing
- Author
-
Brouwer, L., primary, Juchno, M., additional, Arbelaez, D., additional, Ferracin, P., additional, and Vallone, G., additional
- Published
- 2022
- Full Text
- View/download PDF
47. Prevalidation of the cAMP-PTx reporter assay for quantitative assessment of pertussis toxin activity
- Author
-
de Brouwer, L., primary, David, D., additional, Espitia Ballestas, M., additional, Sloots, A., additional, and Hoonakker, M.E., additional
- Published
- 2022
- Full Text
- View/download PDF
48. Electromechanical Analysis for the Integration of a Nb3Sn and a Bi-2212 CCT Dipole Magnet for a Hybrid Magnet Test
- Author
-
Fajardo, L. Garcia, Shen, T., Hafalia, A., Arbelaez, D., Brouwer, L., Ferracin, P., Prestemon, S., and Fernandez, J. Rudeiros
- Abstract
Within the U.S. Magnet Development Program, LBNL is planning to fabricate and test hybrid magnets combining Nb
3 Sn and Bi-2212 canted-cosine theta (CCT) magnets. The first planned hybrid magnet test integrates a 1 m long, 90 mm bore Nb3 Sn dipole magnet (CCT5), and a 39 cm long, 30.8 mm bore Bi-2212 dipole magnet (BIN5c), which are already fabricated and were tested individually. The second planned hybrid magnet test integrates a 1.5 m long, 120 mm bore Nb3 Sn dipole magnet (CCT6), still under design, and a 1 m long, 40 mm bore Bi-2212 dipole magnet (BiCCT1), which is under fabrication. This work gives an update of the status of the Bi-2212 CCT magnet program, and focuses on the first hybrid magnet (CCT5/BIN5c). The electromagnetic and mechanical analysis of the CCT5/BIN5c hybrid magnet is presented, as well as the proposed mechanical assembly process. The quench protection strategy associated with the hybrid magnet test is also presented.- Published
- 2023
- Full Text
- View/download PDF
49. 3D Toroidal Field Multipoles for Curved Accelerator Magnets
- Author
-
Brouwer, L and Brouwer, L
- Published
- 2022
50. Stabilization and control of persistent current magnets using variable inductance
- Author
-
Brouwer, L and Brouwer, L
- Abstract
Ultra-stable, tunable magnetic fields are desirable for a wide range of applications in medical imaging, electron microscopy, quantum science, and atomic physics. Superconducting magnets operated in persistent current mode, with device current flowing in a closed superconducting loop disconnected from a power source, are a common approach for applications with the most stringent requirements on temporal field stability. We present a method for active control of this persistent current by means of dynamic inductance change within the superconducting circuit. For a first realization of this general technique, we consider a variable superconducting inductor placed in series with the main magnet. The inductor acts as a dynamic flux storage device capable of transferring flux to or from the main magnet through inductance change. This allows for fine and fast adjustments of the persistent current without the use of thermal switches that limit the speed and accuracy of many present-day methods. With first experiments employing this technique, we demonstrate stabilization of a 1.95 T Nb-Ti round lens for electron microscopy against decay resulting from residual losses in the superconducting circuit, and more generally show flexibility for precise control over the magnitude and waveform of the persistent current.
- Published
- 2022
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.