As the rock continues to cool, there is a critical temperature at which the magnetic anisotropy becomes large enough to keep the moment from wandering : this temperature is called the " blocking temperature " and referred to by the symbol T _ B.
32.
In solid state physics in a non-zero temperature of the states of fine electronic structure determines the magnetic properties ( single-ionic magnetic anisotropy, magnetic susceptibility as a function of temperature ) and thermodynamic ( Schottky-type specific heat, entropy etc . ).
33.
Where is the height of the energy barrier, a product of the magnetic anisotropy energy density and volume; is the Boltzmann constant, the temperature and their product the thermal energy; and is a length of time, characteristic of the material, called the " attempt time " or " attempt period " ( its reciprocal is called the " attempt frequency " ).
