  In order to calculate the reflected EM fields at low amplitudes in iron and
steel, more must be understood about the nature of long wavelength excitations
in these metals. A bulk piece of iron is a very complex material with
microstructure, a split band structure, magnetic domains and crystallographic
textures that affect domain orientation. Probing iron and other bulk
ferromagnetic materials with weak reflected and transmitted inductive low
frequency fields is an easy operation to perform but the responses are
difficult to interpret because of the complexity and variety of the structures
affected by the fields. First starting with a simple single coil induction
measurement and classical EM calculation to show the error is grossly under
estimating the measured response. Extending this experiment to measuring the
transmission of the induced fields allows the extraction of three dispersion
curves which define these internal fields. One dispersion curve yielded an
exceedingly small effective mass of 1.8 10^{-39}kg (1.3 10^{-9} m_e) for those
spin waves. There is a second distinct dispersion curve more representative of
the density function of a zero momentum bound state rather than a propagating
wave. The third dispersion curve describes a magneto-elastic coupling to a very
long wave length propagating mode. These experiments taken together display the
characteristics of a high temperature Bose-Einstein like condensation that can
be initiated by pumping two different states. A weak time dependent field
drives the formation of coupled J=0 spin wave pairs with the reduced effective
mass reflecting the increased size of the coherent state. These field can
dominate induction measurements well past the Curie temperature.
