Open charm and beauty chiral multiplets in QCD

We study the dynamics of the open charm-and beauty mesons using QCD spectral sum rules (QSSR), where we observe the important role of the chiral condensate ((ψ) over bar psi) in the mass-splittings between the scalar-pseudoscalar mesons. Fixing the sum rule parameters for reproducing the well known D(0(-)) and D-s(0-) masses, we re-obtain the running charm quark mass: (m) over bar (c)(m(c)) = 1.13(-0.04)(+0.08) GeV which confirms our recent estimate from this channel [Phys. Lett. B 520 (2001) 115]. Therefore, using sum rules with no-free parameters, we deduce MDs(0+) similar or equal to (2297 +/- 113) MeV, which is consistent with the observed D-s(2317) meson, while a small SU(3) breaking of about 25 MeV for the D-s(0(+)) - D (0(+)) mass-difference has been obtained. We extend our analysis to the B-system and find MB(0+) - MB(0-) similar or equal to (422 +/- 196) MeV confirming our old result from moment sum rules [Phys. Lett. B 210 (1988) 238]. Assuming an approximate (heavy and light) flavour and spin symmetries of the mass-splittings as indicated by our results, we also deduce MDs*(1+) similar or equal to (2440 +/- 113) MeV in agreement with the observed D-sJ(2457). We also get: f(D(0+)) similar or equal to (217 +/- 25) MeV much bigger than f(pi) = 130.6 MeV, while the size of the SU(3) breaking ratio f(Ds(0+))/f(D(0+)) similar or equal to 0.93 +/- 0.02 is opposite to the one of the 0(-) channel of about 1.14. (C) 2004 Elsevier B.V. All rights reserved.