• Corpus ID: 27016664

New Six-Layer Magnetically-Shielded Room for MEG

  title={New Six-Layer Magnetically-Shielded Room for MEG},
  author={David Cohen and U. Schl{\"a}pfer and Seppo P. Ahlfors and Matti S. H{\"a}m{\"a}l{\"a}inen and Eric Halgren},
A high performance magnetically-shielded room (MSR) has been built by Imedco, to house a 4-D MEG system, containing both gradiometers and magnetometers (Vectorview). The MSR consists of three nested enclosures, each consisting of a high-permeability magnetic layer plus an aluminum layer, where special care was given to the junctions of the inner aluminum layer. Measurements of the passive shielding factor yield 1,630 (64dB), 3,600 (71dB), 240,000 (107dB) , and 78,000,000 (158dB) at frequencies… 

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