Oersted (abbreviated as Oe) is the unit of magnetizing field (also known as magnetic field strength or intensity) in the CGS system of units. It is defined as 1000/4π (≈79.5774715) amperes per meter of flux path, in terms of SI units.12345 The oersted is closely related to the gauss, the CGS unit of magnetic field. In a vacuum, 1 Oe = 1 G, whereas in a medium having permeabilityμ, their relation is 1 Oe = μ G. One oersted also equals a magnetomotive force (mmf) of 1 gilbert per centimeter of flux path.
The unit was established by the IEC in 1930 6 in honour of Hans Christian Ørsted, who discovered electromagnetism in 1820. From the Standard Handbook of Electrical Engineers; "It is that magnetic vector quantity at a point in a magnetic field which measures the ability of electric currents or magnetized bodies to produce magnetic induction at the given point."
In SI units, 1 gilbert = 10/4π ampere-turns = about 0.7958 ampere-turn.
The stored energy in a magnet, called magnet performance, or "magnetic energy product", is typically measured in units of megagauss-oersted (MGOe). Units of MGOe are equivalent to megajoules per cubic meter.
