Physics:Momentum flow

A presentation of the momentum vectors in a reaction, or more frequently of the average momentum vectors, by binning them in solid angle variables. This technique has been used for momenta as measured in track devices, or for energy deposition in calorimeter cells, often as an analysis method in jet studies. In some experiments (e⁺e^- collisions), events have been described entirely in terms of the momentum tensor: the eigenvalue analysis (principal components) of the matrix File:Hepb img479.gif gives a reaction-specific ellipsoid (the p_i are momentum components along axis i, and the pair i,j goes through all permutations of coordinate axes).