九大原子核セミナー

2018年1月22日(月) 16:30〜18:00

講師：池田陽一氏(阪大RCNP)

演題："The Tetraquark Candidate Zc(3900) from coupled-channel scat-
tering on the lattice"

場所：ウェスト1号館7階 物理会議室 (W1-A-723室)

概要：
The structure of the tetraquark candidate Zc(3900), which was experimentally reported in e+e- collisions, is studied by the s-wave meson-meson coupled-channel scattering on the lattice.The s-wave interactions among the πJ/ψ, ρηc and DD* channels are derived from (2+1)-flavor dynamical QCD simulations at mπ = 410-700 MeV. It is found that the interactions are dominated by the off-diagonal πJ/ψ-DD* and ρηc-DD* couplings. With the interactions obtained, the s-wave two-body amplitudes and the pole position in the πJ/ψ-ρηc-DD* coupled-channel scattering are calculated. The results show that the Zc(3900) is not a conventional resonance but a threshold cusp. A semiphenomenological analysis with the coupled-channel interaction to the experimentally observed decay mode is also presented to conrm the conclusion.