Establishement of the magnetic flux density standard in the range 100 µT to 1000 µT
The magnetic flux density standard in the range 100 µT to 1000 µT has been established using a standard Helmholtz coil. The ambient magnetic field including earth's magnetic field components inside the room and other noises has been compensated to a level of the order of 100 nT. A circular triaxial Helmholtz coil pair of size nearly 800 mm has been used for compensating the ambient magnetic field. The standard Helmholtz coil of size 300 mm has been placed in the geometrical centre of the triaxial Helmholtz coil pair. The magnetic flux density has been measured using triaxial and single axis fluxgate magnetometers. The coil constant of the standard Helmholtz coil has been found to be 850.6808 ± 0.0036804 µT/A, which is in good agreement with the manufacture's specification viz, 850 µT/A, with an uncertainty of < ± 0.5 %.
Intercomparison of magnetic flux density by means of field coil transfer standard
The coil constant k/sub 0/-i.e. the quotient of magnetic flux density in the coil centre over the coil current-of a Garrett type field coil has been determined in units as maintained by various standard laboratories. Most of the laboratories have also measured the coil constant k(f) as function of frequency up to f=15 kHz.
A slowly rotating coil system for AC field measurements of Fermilab Booster correctors
A method for measurement of rapidly changing magnetic fields has been developed and applied to the testing of new room temperature corrector packages designed for the Fermilab Booster Synchrotron. The method is based on fast digitization of a slowly rotating tangential coil probe, with analysis combining the measured coil voltages across a set of successive magnet current cycles. This paper presents results on the field quality measured for the normal and skew dipole, quadrupole, and sextupole elements in several of these corrector packages.