Heavy meson thresholds in Born-Oppenheimer Effective field theory

We consider heavy meson-antimeson pairs and their coupling to quarkonium in the context of nonrelativistic EFTs incorporating the adiabatic expansion. We work out all the leading order couplings of quarkonium to heavy meson-antimeson pairs and obtain their contributions to the masses and widths of quarkonia. We match the new potentials terms to NRQCD. Using the available lattice data for the coupled system of quarkonium and the lowest laying heavy meson-antimeson pair, we extract the mixing potential and use it to compute numerically the contributions of $D\bar{D}(B\bar{B})$ and $D_s\bar{D}_s(B_s\bar{B}_s)$ to the masses and widths of the charmonium (bottomonium) states for $l=0,1,2$ and up to $n=6$ covering the states in threshold region. When a quarkonium state and a heavy meson-antimeson pair are separated by small energy gaps, their interactions can be described by a threshold EFT with contact interactions. We work out the matching between the two EFTs obtaining the couplings of the threshold EFT in terms of the mixing potential and quarkonium wave functions.Comment: 26 pages, 9 figure

Exotic bottomonium hadronic transitions

We report on a recent computation of the transitions of exotic bottomonium to standard bottomonium and light quark hadrons. We work under the assumption that the $\Upsilon(10753)$ and $\Upsilon(11020)$ can be described as the lowest laying and first excitation $1^{--}$ hybrid bottomonium states, respectively. The computation has two distinct parts: the heavy quark transition matrix elements, which are obtained in a nonrelativistic EFT incorporating the heavy quark, multipole and adiabatic expansions; and the hadronization of the gluonic operators into the light-meson final states. The single mesons production is obtained through the axial anomaly and a standard $\pi^0-\eta-\eta'$ mixing scheme. Two pion and kaon production is obtained by solving the coupled Omn\`es problem. We also present result for semi-inclusive transitions.Comment: 8 pages, 4 figures. Contribution to the proceedings of the conference "15th Quark Confinement and the Hadron Spectrum

Exotic bottomonium hadronic transitions

We report on a recent computation of the transitions of exotic bottomonium to standard bottomonium and light quark hadrons. We work under the assumption that the ϓ(10753) and ϓ(11020) can be described as the lowest laying and first excitation 1− − hybrid bottomonium states, respectively. The computation has two distinct parts: the heavy quark transition matrix elements, which are obtained in a nonrelativistic EFT incorporating the heavy quark, multipole and adiabatic expansions; and the hadronization of the gluonic operators into the light-meson final states. The single mesons production is obtained through the axial anomaly and a standard π0 - η - ηʹ mixing scheme. Two pion and kaon production is obtained by solving the coupled Omnès problem. We also present result for semi-inclusive transitions

Effective field theory for double heavy baryons at strong coupling

We present an effective field theory for doubly heavy baryons that goes beyond the compact heavy diquark approximation. The heavy quark distance r is only restricted to m Q ≫ 1 / r ≫ E bin , where m Q is the mass of the heavy quark and E bin the typical binding energy. This means that the size of the heavy diquark can be as large as the typical size of a light hadron. We start from nonrelativistic QCD, and build the effective field theory at next-to-leading order in the 1 / m Q expansion. At leading order the effective field theory reduces to the Born-Oppenheimer approximation. The Born-Oppenheimer potentials are obtained from available lattice QCD data. The spectrum for double charm baryons below threshold is compatible with most of the lattice QCD results. We present for the first time the full spin averaged double bottom baryon spectrum below threshold based on QCD. We also present model-independent formulas for the spin splittings