Measures to reduce the residual field and field gradient inside a magnetically shielded room by a factor of more than 10

• Autorzy: Voigt J. , Knappe-Grüneberg S. , Schnabel A. , Körber R. , Burghoff M.
• Języki publikacji: EN

Abstrakty

EN

Very low residual magnetic field and field gradients are essential for a number of high resolution fundamental physical experiments and for further improvement of very sensitive magnetic measurement devices. The scope ranges from spin precession experiments, e.g. with ³He or neutrons, to biomagnetic measurements, like magnetoencephalograms, and to low field MR spectroscopy. One method of reducing environmental magnetic noise is to use a magnetically shielded room (MSR). Here, measures are demonstrated to improve residual field and field gradient inside a common MSR by a factor of more than 10 by a specific degaussing procedure, material selection of prefabricated parts and active shielding. The process is independent of the shielding factor and works also properly for heavily shielded rooms.

Słowa kluczowe

EN

magnetic shielding; magnetic shielded room; msr; residual field; residual field gradient; degaussing; demagnetization

• Wydawca: Komitet Metrologii i Aparatury Naukowej PAN
• Czasopismo: Metrology and Measurement Systems
• Rocznik: 2013
• Tom: Vol. 20, nr 2
• Strony: 237--248
• Opis fizyczny: Bibliogr. 15 poz., rys., wykr.

Twórcy

autor

Voigt J.

• Physikalisch-Technische-Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany

autor

Knappe-Grüneberg S.

• Physikalisch-Technische-Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany

autor

Schnabel A.

• Physikalisch-Technische-Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany

autor

Körber R.

• Physikalisch-Technische-Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany

autor

Burghoff M.

• Physikalisch-Technische-Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany

Bibliografia

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• [13] Schnabel, A., et al. (2008). Crucial parameters for better degaussing of magnetically shielded rooms. Biomag poster,
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Uwagi

EN

This work is supported by the Federal Ministry of Education and Research, Bernstein Focus Neurotechnology, Project number 01GQ0852 and by the German Research Foundation (DFG), Project BU-1037/3-1.