The hypothesis that there exists a nonet of scalars mainly composed of a valence quark-antiquark pair and mixed according to near singlet-octet separation : f_0 (980) singlet, a_0^{ +,0,-} (980), K^{ * +,0}_0 (1430), \bar K^{ * -,0}_0 (1430), f_0 (1500) octet, is put to further tests from the three body decays D^{ \pm}, D_{ s}^{ \pm} -> PS^{ \pm} pi^+ pi^- with PS^{ \pm} = pi^{ \pm}, K^{ \pm}. The analysis of decay phases supports the singlet nature of f_0 (980).
Categories: hep-ph