  We propose a systematic procedure to study a generalized linear sigma model
which can give a physical picture of possible mixing between $q{\bar q}$ and
$qq{\bar q}{\bar q}$ low lying spin zero states. In the limit of zero quark
masses, we derive the model independent results for the properties of the Nambu
Goldstone pseudoscalar particles. For getting information on the scalars it is
necessary to make a specific choice of terms. We impose two plausible physical
criteria - the modeling of the axial anomaly and the suppression of effective
vertices representing too many fermion lines - for limiting the large number of
terms which are allowed on general grounds. We calculate the tree-level
spectrum based on the leading terms in our approach and find that it
prominently exhibits a very low mass isosinglet scalar state. Finally we point
out that the low energy result for scattering of pions continues to hold in the
general version of the model.

High Energy Physics - Phenomenology