The a(0)(980), a(0)(1450) and K-0*(1430) scalar decay constants and the isovector scalar spectrum

The scalar correlator Pi(q(2)) = i integral d(4)xe(iq . x) [00] (with J = t heta(mu)((d) over bar gamma(mu)u)) is studied using a class of finite energ y sum rules shown recently to be very well satisfied in the vector isovecto r channel. The values of the a(0) scaler decay constants extracted in this analysis, which describe the couplings of the a(0)(980) and a(0)(1450) to t he current J, are shown to be comparable, strongly disfavoring any scenario in which the a(0)(980) is interpreted as a loosely bound K (K) over bar mo lecule and the a(0)(1450) is assigned to the same flavor multiplet as the K -0*(1430). The a(0) decay constants are also compared to the analogous deca y constant describing the coupling of the K-0*(1430) to the divergence of t he strange vector current, J(s) = theta(mu)((s) over bar gamma(mu)u) (which may be obtained from experimental K-e3 and K-pi phase shift data) and impl ications of the relative magnitudes far the interpretation of the nature of the a(0) states discussed. (C) 1999 Published by Elsevier Science B.V. All rights reserved.