A case for hidden bb¯ tetraquarks based on e+e−→bb¯ cross section between s=10.54 and 11.20 GeV

We study the spectroscopy and dominant decays of the bottomonium-like tetraquarks (bound diquarks–antidiquarks), focusing on the lowest lying P-wave [bq][b¯q¯] states Y[bq]Y[bq] (with q=u,dq=u,d), having JPC=1−−JPC=1−−. To search for them, we analyse the BaBar data [1] obtained during an energy scan of the e+e−→bb¯ cross section in the range of s=10.54 to 11.20 GeV. We find that these data are consistent with the presence of an additional bb¯ state Y[bq]Y[bq] with a mass of 10.90 GeV and a width of about 30 MeV apart from the ϒ(5S)ϒ(5S) and ϒ(6S)ϒ(6S) resonances. A closeup of the energy region around the Y[bq]Y[bq]-mass may resolve this state in terms of the two mass eigenstates, Y[b,l]Y[b,l] and Y[b,h]Y[b,h], with a mass difference, estimated as about 6 MeV. We tentatively identify the state Y[bq](10900)Y[bq](10900) from the RbRb-scan with the state Yb(10890)Yb(10890) observed by Belle [2] in the process e+e−→Yb(10890)→ϒ(1S,2S)e+e−→Yb(10890)→ϒ(1S,2S)π+π−π+π− due to their proximity in masses and decay widths.