Abstract
We interpret the X_1(2900) as an S-wave {bar{D}}_1K molecular state in the Bethe–Salpeter equation approach with the ladder and instantaneous approximations for the kernel. By solving the Bethe–Salpeter equation numerically with the kernel containing one-particle-exchange diagrams and introducing three different form factors (monopole, dipole, and exponential form factors) in the verties, we find the bound state exists. We also study the decay width of the decay X_1(2900) to D^-K^+.
Highlights
Two new open flavor states were observed by LHCb collaboration in the D− K + invariant mass distribution of B+ → D+ D− K +, and the parameters are determined to be [1]
Since the resonances X0(2900) and X1(2900) are observed in the D− K + channel, they should be manifestly exotic and have minimal quark content cdus. These two states are new fully open flavor states after the discovery of X (5568), which was reported by D0 collaboration in the Bsπ invariant mass distribution in 2016
We can solve the BS equation numerically and study whether the S-wave D 1 K bound state exists or not. It can be seen from Eq (14) that there is only one free parameter in our model, the cutoff, which enters through various phenomenological form factors in Eq (10)
Summary
Two new open flavor states were observed by LHCb collaboration in the D− K + invariant mass distribution of B+ → D+ D− K +, and the parameters are determined to be [1]. Since the resonances X0(2900) and X1(2900) are observed in the D− K + channel, they should be manifestly exotic and have minimal quark content cdus These two states are new fully open flavor states after the discovery of X (5568) (subd), which was reported by D0 collaboration in the Bsπ invariant mass distribution in 2016. From the QCD Sum Rules, the X0(2900) and X1(2900) were studied in molecular and diquark-antidiquark tetraquark pictures, respectively, and the results for masses are in good agreement with the observed masses in the experiment [14].
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
