  The use of energy flow is investigated as a diagnostic tool for determining
the color SU(3) representation of new resonances. It is found that the pattern
of soft gluon radiation into a rapidity gap depends on color flow in the hard
scattering, and reflects the gauge content of new physics. The massive soft
anomalous dimension matrix for rapidity gap events is introduced for describing
soft gluon emission analytically in heavy quark pair production. A gap fraction
is used for quantifying the amount of soft radiation into the gap region. In
general, the results illustrate that radiation is greater for a singlet
resonance than for an octet. Especially, it is found that the quantitative
difference is quite distinguishable for spin-1 resonances, depending on the
gauge content in the new sector.
