Branching fractions of $$B^-\rightarrow D^-X_{0,1}(2900)$$ and their implications

Abstract

The exotic states $$X_{0,1}(2900)$$ X 0 , 1 ( 2900 ) with the quark flavor of $$cs\bar{u}\bar{d}$$ c s u ¯ d ¯ are recently observed in the mass spectrum of $$D^+K^-$$ D + K - in $$B^-\rightarrow D^-D^+K^-$$ B - → D - D + K - by the LHCb collaboration. To explore the nature of $$X_{0,1}(2900)$$ X 0 , 1 ( 2900 ) , except for analyzing their masses and decay widths as usually did in literatures, the study of their production mechanism in B-meson weak decays would provide another important information. The amplitude of $$B^-\rightarrow D^- X_{0,1}$$ B - → D - X 0 , 1 is non-factorizable. We consider the final-state-interaction effects and calculate them via the rescattering mechanism. The measured branching fractions of $$B^-\rightarrow D^- X_{0,1}$$ B - → D - X 0 , 1 are revealed. It is manifested by $${B}^-\rightarrow \Lambda _c^-\Xi _c^{(\prime )0}$$ B - → Λ c - Ξ c ( ′ ) 0 and $$\Lambda _b^0\rightarrow P_c^+K^-$$ Λ b 0 → P c + K - that the rescattering mechanism can result in the relatively large branching fractions. The similar processes of $$B^-\rightarrow \pi ^-X_{0,1}$$ B - → π - X 0 , 1 are also analyzed. The isospins of $$X_{0,1}$$ X 0 , 1 can be investigated by $$B\rightarrow DX_{0,1}^{\pm ,0}$$ B → D X 0 , 1 ± , 0 decays.

Mass spectrum and strong decays of tetraquark $${\bar{c}}{\bar{s}} qq$$ states

“…The study of other properties such as production and decay patterns become essential, which are very sensitive to the inner structures of the multi-quark system. There are several theoretical studies about the decays and productions [15,18,22,34,35]. For instance, the authors in Ref.…”

“…So far, their inner structures and properties are still not clear. One explanation is that the enhancement might be solely from the rescattering effects of theD * K * →DK orD 1 K ( * ) →DK channels [13][14][15]. Another explanation is the genuine resonance [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30], either the loosely bound molecular states or the compact tetraquark states.…”

Heavy Flavour Physics and CP Violation at LHCb: a Ten-Year Review

“…It is noted that these two X states contribute up to 35% of the total B + → D + D − K + decay branching fraction, a magnitude similar to those of conventional charmonia in the decay. A final state rescattering effect is considered to explain such a large branching fraction [420]. The observation of X states in the B + → D + D − K + decay opens a new avenue for studies of exotic hadrons composed of four different quark flavours [421][422][423][424][425][426][427][428][429][430][431][432][433][434].…”

Magnetic moment of the $X_1(2900)$ state in the diquark-antidiquark picture

“…The production and decay properties of these states were investigated in Refs. [17][18][19][20], as well. One can also consult Refs.…”