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New Standard Magnetic Observation System of Kakioka （KASMMER）
Yanagihara, K., Kawamura, M., Sano, Y. & Kuboki, T.
A new system, which is called KASMMER (Kakioka Automatic Standard Magnetometer), has been constructed for the standard magnetic observation at Kakioka. The main equipment consists of four optical pumping magnetometers, a proton magnetometer, the DI-72 (newly designed magnetometer theodolite for the absolute value determination of the declination and the dip) and a computer system. The whole system is operated automatically except the DI-72. Digital data of the geomagnetic field is obtained with an absolute accuracy of ０.１γ and with the least possible delay.
Four optical pumping magnetometers can give the finest possible time resolution for each component of the geomagnetic field at the present, though minute-values only are utilized for the primary data processing in routine operation, and also make it possible to compare the measured value of a component with the calculated one from the other components in order to watch the operation or to check the preciseness of the instruments. The ASMO method proposed by Alldredge also can be utilized when any of the optical pumping magnetometers meets trouble. Instrumental parameter of the optical pumping magnetometer is calibrated by the proton magnetometer and the DI-72.
The DI-72 determines the declination and the dip with an absolute accuracy of 1". A vector proton magnetometer MO-P installed in 1963 supplements calibration measurements.
All data is processed in the computer system comprising two mini-computers and many accessories. The processed data is stored initially in the magnetic disc memory and then filed in the digital magnetic tape. A curve follower and a curve plotter facilitate the analog-to-digital and digital-to-analog conversion of internal and external data.
Test operations for a few months have given satisfactory results.
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