The χcJ decay to ϕK⁎K¯,ϕh1(1380) testing the nature of axial vector meson resonances

Abstract

We perform a theoretical study of the χ→ϕKK¯→ϕKπK¯ reaction taking into account the KK¯ final state interaction, which in the chiral unitary approach is responsible, together with its coupled channels, for the formation of the low lying axial vector mesons, in this case the h(1380) given the selection of quantum numbers. Based on this picture we can easily explain why in the χ decay the h(1380) resonance is not produced, and, in the case of χ and χ decay, why a dip in the KπK mass distribution appears in the 1550-1600 MeV region, that in our picture comes from a destructive interference between the tree level mechanism and the rescattering that generates the h(1380) state. Such a dip is not reproduced in pictures where the nominal h(1380) signal is added incoherently to a background, which provides support to the picture where the resonance appears from rescattering of vector-pseudoscalar components.