All-heavy tetraquarks with different flavors

In a nonrelativistic potential quark model framework, we carry out a precise calculation of the mass spectrum of the all-heavy tetraquarks with different flavors, bbb̄c̄, ccc̄b̄, bbc̄c̄, and bcb̄c̄, by adopting the explicitly correlated Gaussian method. A complete mass spectrum for the $1S$ states is obtained. For the bbb̄c̄, ccc̄b̄, bbc̄c̄, and bcb̄c̄ systems, the $1S$ states are predicted to lie in the mass ranges of ~(16.06,16.14), ~(9.65,9.74), ~(12.89,12.94), and ~(12.75,12.99)~GeV, respectively. Moreover, by using the obtained masses and wave functions, we evaluate the fall-apart decay properties within a quark-exchange model. The results show that the $1S$ states of the all-heavy tetraquarks with different flavors may have narrow fall-apart decay widths, which range from a few tenths to several MeV. Some all-heavy tetraquarks with different flavors could be search for at LHC in their optimal fall-apart decay channels, such as Υ J/ψ, Υ Bc⁻, and J/ψ Bc⁺.