### Abstract

When a magnet generating highly homogeneous magnetic field is designed, a shimming is required. The shimming is usually performed so that the magnetic field only in the axis direction is compensated by iron pieces and/or coils. The compensation is commonly achieved by eliminating the coefficients of the spherical harmonics expansion of the magnetic field generated by the main magnet. Some papers showed the coefficients of the spherical harmonics expansion in only the z-direction for passive shimming. However, recently some magnets generate a magnetic field tilted from the z-axis, such as a magic-angle-spinning nuclear magnetic resonance/MRI. It is, therefore, necessary to eliminate the coefficients of the spherical harmonics expansion in the x-and y-direction.

Original language | English |
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Article number | 6749021 |

Journal | IEEE Transactions on Magnetics |

Volume | 50 |

Issue number | 2 |

DOIs | |

Publication status | Published - Feb 2014 |

Externally published | Yes |

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### Keywords

- Magnetic moment
- MRI
- nuclear magnetic resonance (NMR)
- passive shimming
- spherical harmonics expansion

### ASJC Scopus subject areas

- Electrical and Electronic Engineering
- Electronic, Optical and Magnetic Materials

### Cite this

*IEEE Transactions on Magnetics*,

*50*(2), [6749021]. https://doi.org/10.1109/TMAG.2013.2276736

**Passive shimming by eliminating spherical harmonics coefficients of all magnetic field components generated by correction iron pieces.** / Noguchi, So; Kim, Seok Beom; Hahn, Seungyong; Iwasa, Yukikazu.

Research output: Contribution to journal › Article

*IEEE Transactions on Magnetics*, vol. 50, no. 2, 6749021. https://doi.org/10.1109/TMAG.2013.2276736

}

TY - JOUR

T1 - Passive shimming by eliminating spherical harmonics coefficients of all magnetic field components generated by correction iron pieces

AU - Noguchi, So

AU - Kim, Seok Beom

AU - Hahn, Seungyong

AU - Iwasa, Yukikazu

PY - 2014/2

Y1 - 2014/2

N2 - When a magnet generating highly homogeneous magnetic field is designed, a shimming is required. The shimming is usually performed so that the magnetic field only in the axis direction is compensated by iron pieces and/or coils. The compensation is commonly achieved by eliminating the coefficients of the spherical harmonics expansion of the magnetic field generated by the main magnet. Some papers showed the coefficients of the spherical harmonics expansion in only the z-direction for passive shimming. However, recently some magnets generate a magnetic field tilted from the z-axis, such as a magic-angle-spinning nuclear magnetic resonance/MRI. It is, therefore, necessary to eliminate the coefficients of the spherical harmonics expansion in the x-and y-direction.

AB - When a magnet generating highly homogeneous magnetic field is designed, a shimming is required. The shimming is usually performed so that the magnetic field only in the axis direction is compensated by iron pieces and/or coils. The compensation is commonly achieved by eliminating the coefficients of the spherical harmonics expansion of the magnetic field generated by the main magnet. Some papers showed the coefficients of the spherical harmonics expansion in only the z-direction for passive shimming. However, recently some magnets generate a magnetic field tilted from the z-axis, such as a magic-angle-spinning nuclear magnetic resonance/MRI. It is, therefore, necessary to eliminate the coefficients of the spherical harmonics expansion in the x-and y-direction.

KW - Magnetic moment

KW - MRI

KW - nuclear magnetic resonance (NMR)

KW - passive shimming

KW - spherical harmonics expansion

UR - http://www.scopus.com/inward/record.url?scp=84900085294&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84900085294&partnerID=8YFLogxK

U2 - 10.1109/TMAG.2013.2276736

DO - 10.1109/TMAG.2013.2276736

M3 - Article

VL - 50

JO - IEEE Transactions on Magnetics

JF - IEEE Transactions on Magnetics

SN - 0018-9464

IS - 2

M1 - 6749021

ER -