Invariant Box-Parameterization of Neutrino Oscillations
  The model-independent "box" parameterization of neutrino oscillations is examined. The invariant boxes are the classical amplitudes of the individual oscillating terms. Being observables, the boxes are independent of the choice of parameterization of the mixing matrix. Emphasis is placed on the relations among the box parameters due to mixing--matrix unitarity, and on the reduction of the number of boxes to the minimum basis set. Using the box algebra, we show that CP-violation may be inferred from measurements of neutrino flavor mixing even when the oscillatory factors have averaged. General analyses of neutrino oscillations among $n\ge 3$ flavors can readily determine the boxes, which can then be manipulated to yield magnitudes of mixing matrix elements. 
Thomas J. Weiler and DJ Wagner