Speaker
Floriana Giannuzzi
(University of Bari and INFN)
Description
The quark-antiquark potential obtained in a gauge/gravity (AdS/QCD)
approach is inserted in a Salpeter equation to determine heavy hadron
masses. The parameters of the model are fixed fitting the known spectrum
of the $S$-wave mesons in the sector of heavy-light quarks, charmonium and
bottomonium. The predicted mass of $\eta_b$ is in agreement with the
subsequent observation by BaBar Collaboration. A discussion of heavy
tetraquark masses is also presented, motivated by the possibility of a
diquark-antidiquark structure for some states. The decay constants of
charmonium and bottomonium are determined: they control the processes
$\eta (nS)_{c/b}\rightarrow\gamma\gamma$ and
$\psi(nS)/\Upsilon(nS)\rightarrow \ell\bar \ell$.
Finally, the masses of baryons comprising two heavy quarks are computed
in the same model, assuming a quark-diquark scheme; these states are
predicted to exist by the quark model, but so far there is only one
experimental candidate, $\Xi_{cc}$, observed by the Selex Collaboration.
based on:
Eur.\ Phys.\ J.\ C {\bf 57}, 569 (2008)
Phys.\ Rev.\ D {\bf 78}, 117501 (2008)
arXiv:0902.4624 [hep-ph], to appear on Phys.\ Rev.\ D {\bf 79}, 094002 (2009)
Primary author
Floriana Giannuzzi
(University of Bari and INFN)
