Investigating tetraquarks composed of $$us\bar{d}\bar{b}$$ usd¯b¯ and $$ud\bar{s}\bar{b}$$ uds¯b¯

Abstract

Abstract In the framework of the quark delocalization color screening model, we investigate tetraquarks composed of $$us\bar{d}\bar{b}$$ usd¯b¯ and $$ud\bar{s}\bar{b}$$ uds¯b¯ in two structures: meson-meson structure and diquark–antidiquark structure. Neither bound state nor resonance state is found in the system composed of $$us\bar{d}\bar{b}$$ usd¯b¯ . The reported X(5568) cannot be explained as a molecular state or a diquark–antidiquark resonance of $$us\bar{d}\bar{b}$$ usd¯b¯ in present calculation. However, two bound states of the diquark–antidiquark structure are obtained in the tetraquarks system composed of $$ud\bar{s}\bar{b}$$ uds¯b¯ : an $$IJ=00$$ IJ=00 state with the mass of 5701 MeV, and an $$IJ=01$$ IJ=01 state with the mass of 5756 MeV, which maybe the better tetraquark states with four different flavors. Our results indicate that the diquark–antidiquark configuration would be a good choice for the tetraquarks $$ud\bar{s}\bar{b}$$ uds¯b¯ with quantum numbers $$IJ=00$$ IJ=00 and $$IJ=01$$ IJ=01 . The tetraquarks composed of $$ud\bar{s}\bar{b}$$ uds¯b¯ is more possible to form bound states than the one composed of $$us\bar{d}\bar{b}$$ usd¯b¯ . These bound states are worth investigating in future experiments.