0000000000728503
AUTHOR
Francisco Fernández González
Microscopic NN-π NN*(1440) transition potential: determination of πNN*(1440) and πNN*(1440) coupling constants
A NN→NN∗(1440) transition potential, based on an effective quark-quark interaction and a constituent quark cluster model for baryons, is derived in the Born-Oppenheimer approach. The potential shows significant differences with respect to those obtained by a direct scaling of the nucleon-nucleon interaction. From its asymptotic behavior we extract the values of πNN∗(1440) and σNN∗(1440) coupling constants in a particular coupling scheme.
Multiquark description of the D-sJ(2860) and D-sJ(2700)
Within a theoretical framework that accounts for all open-charm mesons, including the D-0*(2308), the D-sJ*(2317), and the D-sJ(2460), we analyze the structure and explore possible quantum number assignments for the D-sJ(2860) and the D-sJ(2700) mesons reported by BABAR and Belle Collaborations. The open-charm sector is properly described if considered as a combination of conventional quark-antiquark states and four-quark components. All negative parity and 2(+) states can be understood in terms only of q (q) over bar components, however the description of the 0(+) and 1(+) mesons is improved whenever the mixing between two- and four-quark configurations is included. We analyze all possible…
Describing non-QQ candidates
Despite the apparent simplicity of meson spectroscopy there are some states which cannot be accommodated in the usual q (q) over bar structure. Among them there are either exotic states as the X(1600) or the recently measured charm states D-sJ(*) and X(3872) and some of the light scalar mesons. In this work we present a possible description of these states in terms of tetraquarks.