Possibility of T_{cbar{s}}(2900) as the resonance-like structure induced by threshold effects

Abstract

We investigate the process Brightarrow bar{D}D_s pi via several rescattering processes. It is shown that the triangle singularity (TS) peak around the D^*K^* threshold generated from the chi _{c1}K^* D^* loop is relatively narrow, which may simulate the resonance-like structure T_{cbar{s}}(2900) recently observed by LHCb in the D_spi spectrum. However, the TS peak around the D_s^*rho threshold generated from the D^{**} D_s^* rho loop is smoothed by the broad width of rho , which itself can hardly describe the T_{cbar{s}}(2900) structure. A non-resonance TS signal around the DK threshold generated from the chi _{c0}K D loop is also predicted.