We construct the U-l(3) X U-R(3) effective lagrangian which encodes the dyn
amics of the low energy pseudoscalar excitations in the Color-Flavor-Lockin
g superconducting phase of QCD at finite quark density. We include the effe
cts of instanton-induced interactions and study the mass pattern of the pse
udoscalar masons. A tentative comparison with the analytical estimate for t
he gap suggests that some of these low energy momentum modes are not stable
for moderate values of the quark chemical potential mu. (C) 2000 Elsevier
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