Triangle singularity and a possible ϕp resonance in the decay

作者：Ju-Jun Xie; Feng-Kun Guo

来源：Physics Letters B, 2017, 774: 108-113.

We study the Λc+→π0ϕp decay by considering a triangle singularity mechanism. In this mechanism, the Λ+c decays into the K⁎Σ⁎(1385), the Σ⁎(1385) decays into the π0Σ (or Λ), and then the K⁎Σ (or Λ) interact to produce the ϕp in the final state. This mechanism produces a peak structure around 2020 MeV. In addition, the possibility that there is a hidden-strange pentaquark-like state is also considered by taking into account the final state interactions of K⁎Λ, K⁎Σ, and ϕp. We conclude that it is difficult to search for the hidden-strange analogue of the Pc states in this decay. However, we do expect nontrivial behavior in the ϕp invariant mass distribution. The predictions can be tested by experiments such as BESIII, LHCb and Belle-II.