Open AccessA new high‐precision furnace for paleomagnetic and paleointensity studies: Minimizing magnetic noise generated by heater currents inside traditional thermal demagnetizers
Author(s) -
Zheng Zhong,
Zhao Xixi,
Horng ChorngShern
Publication year - 2010
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2010gc003100
Subject(s) - demagnetizing field , geology , thermal , waveform , noise (video) , magnetic field , amplitude , paleomagnetism , acoustics , geophysics , current (fluid) , spurious relationship , magnetization , voltage , electrical engineering , optics , physics , thermodynamics , oceanography , quantum mechanics , artificial intelligence , computer science , image (mathematics) , engineering , machine learning
Although magnetic noise fields generated by heater currents in thermal demagnetizers have been noticed for a long time, no satisfactory tests have been conducted to quantify their effects. Toward this end, we have developed a new high‐precision thermal demagnetizer that greatly reduces the magnetic noise field. We show the data quality generated by the new oven and the comparative results on several real samples that demonstrate the effects of the magnetic noise field due to heater currents. The properties of the spurious magnetization emanating from the heater currents critically depend on the decay rate of amplitude and its waveform of electric power which is delivered to oven coils at the end of the heating stage of thermal demagnetization. These results also illustrate the potential applications of this new instrument in paleomagnetism and paleointensity studies.