We study the Belle reaction Ξc+ββΞβΟ+Ο+ looking at the
mass distribution of Ο+Ξ, where clear signals for the Ξ(1620) and
Ξ(1690) resonances are seen. These two resonances are generated dynamically
from the interaction in coupled channels of ΟΞ,KΛΞ,KΛΞ£ and Ξ·Ξ within the chiral unitary approach. Yet, the weak decay
process at the quark level, together with the hadronization to produce pairs of
mesons, does not produce the ΟΟΞ final state. In order to produce
this state one must make transitions from the KΛΞ,KΛΞ£
and Ξ·Ξ components to ΟΞ, and this interaction is what produces
the resonances. So, the reaction offers a good test for the molecular picture
of these resonances. Adding the contribution of the Ξβ(1530) and some
background we are able to get a good reproduction of the mass distribution
showing the signatures of the two resonances as found in the experiment.Comment: 15 pages, 8 figures, 2 tables; v2: discussion added, references
added, version to appear in Eur.Phys.J.