caa a22 4500 60554557X CHVBK 20210128100936.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s00723-015-0691-2 doi (NATIONALLICENCE)springer-10.1007/s00723-015-0691-2 Shim Coils Design for Halbach Magnet Based on Target Field Method [Elektronische Daten] [Yajie Xu, Qiaoyan Chen, Guangcai Zhang, Zhiguo Pei, Xiaodong Yang] A modified target field method is presented to the construction of shim and gradient coils for Halbach-type magnet featuring cylindrical magnet and transversal magnetic field direction. With Biot-Savart law, magnetic field is deduced from current density distribution, and two solutions corresponding to relations between spherical harmonic functions degree m and current density degree k, namely $$m=k\pm 1$$ m = k ± 1 are derived. Then combined with magnetic field distribution of target points, current density coefficient $$U_{\rm q}$$ U q is adopted to calculate stream function, based on which the coils' structure can be obtained. An appropriate objective function integrating dissipated energy and relative error is utilized to further improve the design. Examples of X2-Y2 and Y coils indicate that solution corresponding to $$m=k-1$$ m = k - 1 exhibits good agreement with theory in terms of obtaining lower dissipated energy and smaller error rate, suggesting that the algorithm provides an effective, preferable approach for the design of Halbach shim coils. Springer-Verlag Wien, 2015 Xu Yajie Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut Chen Qiaoyan Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut Zhang Guangcai Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut Pei Zhiguo Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut Yang Xiaodong Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut Applied Magnetic Resonance Springer Vienna 46/7(2015-07-01), 823-836 0937-9347 46:7<823 2015 46 723 https://doi.org/10.1007/s00723-015-0691-2 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00723-015-0691-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Xu Yajie Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut NATIONALLICENCE 700 1- Chen Qiaoyan Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut NATIONALLICENCE 700 1- Zhang Guangcai Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut NATIONALLICENCE 700 1- Pei Zhiguo Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut NATIONALLICENCE 700 1- Yang Xiaodong Department of Medical Imaging, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, Jiangsu, China aut NATIONALLICENCE 773 0- Applied Magnetic Resonance Springer Vienna 46/7(2015-07-01), 823-836 0937-9347 46:7<823 2015 46 723