Note: Magnetic noise from the inner wall of a magnetically shielded room

被引：8

作者：

Khan, Sheraz ^{[1
,2
]}

Cohen, David ^{[2
,3
,4
]}

机构：

[1] Harvard Univ, Sch Med, Massachusetts Gen Hosp, Dept Neurol, Boston, MA 02129 USA

[2] Harvard Univ, MIT, Massachusetts Gen Hosp, AA Martinos Ctr Biomed Imaging, Boston, MA 02129 USA

[3] Harvard Univ, Sch Med, Massachusetts Gen Hosp, Dept Radiol, Boston, MA 02129 USA

[4] MIT, Francis Bitter Magnet Lab, Cambridge, MA 02139 USA

来源：

REVIEW OF SCIENTIFIC INSTRUMENTS | 2013年 / 84卷 / 05期

关键词：

MAGNETOENCEPHALOGRAPHY;

D O I：

10.1063/1.4802845

中图分类号：

TH7 [仪器、仪表];

学科分类号：

0804 ; 080401 ; 081102 ;

摘要：

We measured the thermal magnetic noise generated by the inner high-permeability wall of a magnetically shielded room. This room houses a magnetoencephalogram (MEG), which contains 102 "small" identical magnetometers. For the measurement, we created two large magnetometers by summing the outputs of 46 magnetometers equally on the helmet's left and right side, to look at the summed noise of the right and left vertical walls. From these summed outputs, we calculated the rms noise amplitude due to all six walls at the MEG location to be similar to 0.5 f T/root Hz at 100 Hz, only slowly rising with lower frequency. This is well below the system noise of each small MEG magnetometer, hence is negligible for the MEG. (C) 2013 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.

引用

页数：3