Bc± decays into tetraquarks Bc± DECAYS into TETRAQUARKS A. ALI et al

The recent observation by the D0 collaboration of a narrow structure X(5568) consisting of four different quark flavors bdus, has not been confirmed by LHCb. In the tightly bound diquark model, we estimate the lightest bdus, 0+ tetraquark at a mass of about 5770 MeV, approximately 200 MeV above the reported X(5568), and just 7 MeV below the BK¯ threshold. The charged tetraquark is accompanied by I=1 and I=0 neutral partners almost degenerate in mass. A bdus, S-wave, 1+ quartet at 5820 MeV is implied as well. In the charm sector, cdus, 0+ and 1+ tetraquarks are predicted at 2365 and 2501 MeV, about 40–50 MeV heavier than Ds0(2317) and Ds1(2460). The bdus tetraquarks can be searched in the hadronic debris of a jet initiated by a b. However, some of them may also be produced in Bc decays, Bc→Xb0+π with the subsequent decays Xb0→Bs+π, giving rise to final states such as Bsπ+π0. We also emphasize the importance of Bc decays as a source of bound hidden charm tetraquarks, such as Bc→X(3872)+π.