A survey of existing instrumentation and developments is presented
emphasizing instrumentation for in-flight calibration of vector
magnetometers on magnetic mapping missions. Proton free or forced
precession magnetometers are at the focus as calibration
references, because the proton gyromagnetic ratio is a basic
atomic constant for the SI units of magnetic and electric current.
The classical proton free precession, the Overhauser forced
oscillation and a new field cycling Overhauser are presented.
Alkali metal vapor magnetometers, although not absolute in the
same sense as the classical proton magnetometer, offer stability
and resolution well suited for the calibration purposes. Recent
developments are discussed. The metastable Helium magnetometer
also offers quasi-absolute scalar measurements, and the use of
semiconductor tuned lasers replacing an RF-excited Helium lamp
holds great promise for improved accuracy and reduced power
|Publication status||Published - 1998|