Triangle singularity as the origin of $$X_0(2900)$$ X 0 ( 2900 ) and $$X_1(2900)$$ X 1 ( 2900 ) observed in $$B^+\rightarrow D^+ D^- K^+$$ B + → D + D - K +

• Main Authors: Xiao-Hai Liu, Mao-Jun Yan, Hong-Wei Ke, Gang Li, Ju-Jun Xie
• Format: Article
• Language: English
• Published: SpringerOpen 2020-12-01
• Series: European Physical Journal C: Particles and Fields
• Online Access: https://doi.org/10.1140/epjc/s10052-020-08762-6

Abstract The LHCb collaboration recently reported the observation of a narrow peak in the $$D^- K^+$$ D - K + invariant mass distributions from the $$B^+\rightarrow D^+ D^- K^+$$ B + → D + D - K + decay. The peak is parameterized in terms of two resonances $$X_0(2900)$$ X 0 ( 2900 ) and $$X_1(2900)$$ X 1 ( 2900 ) with the quark contents $${\bar{c}}{\bar{s}}ud$$ c ¯ s ¯ u d , and their spin-parity quantum numbers are $$0^+$$ 0 + and $$1^-$$ 1 - , respectively. We investigate the rescattering processes which may contribute to the $$B^+\rightarrow D^+ D^- K^+$$ B + → D + D - K + decays. It is shown that the $$D^{*-}K^{*+}$$ D ∗ - K ∗ + rescattering via the $$\chi _{c1}K^{*+}D^{*-}$$ χ c 1 K ∗ + D ∗ - loop and the $${\bar{D}}_{1}^{0}K^{0}$$ D ¯ 1 0 K 0 rescattering via the $$D_{sJ}^{+}{\bar{D}}_{1}^{0}K^{0}$$ D sJ + D ¯ 1 0 K 0 loop can simulate the $$X_0(2900)$$ X 0 ( 2900 ) and $$X_1(2900)$$ X 1 ( 2900 ) with consistent quantum numbers. Such phenomena are due to the analytical property of the scattering amplitudes with the triangle singularities located to the vicinity of the physical boundary.