An open charm tetraquark candidate: note on $X_0(2900)$

Abstract

Motivated by the LHCb's very recent observation of exotic $X_0(2900)$ in the $B^{+}\to D^{+}{D}^{-}{K}^{+}$ process, for which could be a good open charm $ud\bar{c}\bar{s}$ tetraquark candidate, we endeavor to investigate its possibility by means of QCD sum rules. In technique, four configurations of interpolating currents with $J^P=0^{+}$ are studied for the $ud\bar{c}\bar{s}$ tetraquark state. In the end, mass values are calculated to be $2.76_{-0.23}^{+0.16}\text{mbox}GeV$ for the axial vector diquark-axial vector antidiquark configuration and $2.75_{-0.24}^{+0.15}\text{mbox}GeV$ for the scalar diquark-scalar antidiquark configuration, both of which are consistent with the experimental data $2.866\pm 0.007\pm 0.002\text{mbox}GeV$ of $X_0(2900)$ in view of the uncertainty. These results support that $X_0(2900)$ could be a $0^{+}$ tetraquark state with open charm flavor.

Comments: 8 pages, 4 figures; version accepted for publication in Phys. Rev. D