Differential magnetic moment
= Differential magnetic moment
{title2=$\Delta\mu=-\partial(E_2-E_1)/\partial B$}
With <energy> convention $E=-\boldsymbol\mu\cdot\mathbf B$, the difference of physical moments is the negative derivative of a transition <energy>. Some trapping conventions instead call the positive <energy> slope an effective magnetic moment. The sign convention must be stated; either gives the same absolute sensitivity of transition <frequency> to a field fluctuation.