Υspectrum andmbfrom full lattice QCD

We show results for the ${\rm Y}$ spectrum calculated in lattice QCD including for the first time vacuum polarization effects for light $u$ and $d$ quarks as well as $s$ quarks. We use gluon field configurations generated by the MILC collaboration. The calculations compare the results for a variety of $u$ and $d$ quark masses, as well as making a comparison to quenched results (in which quark vacuum polarization is ignored) and results with only $u$ and $d$ quarks. The $b$ quarks in the ${\rm Y}$ are treated in lattice Nonrelativistic QCD through NLO in an expansion in the velocity of the $b$ quark. We concentrate on accurate results for orbital and radial splittings where we see clear agreement with experiment once $u$, $d$ and $s$ quark vacuum polarization effects are included. This now allows a consistent determination of the parameters of QCD. We demonstrate this consistency through the agreement of the ${\rm Y}$ and $B$ spectrum using the same lattice bare $b$ quark mass. A one-loop matching to continuum QCD gives a value for the $b$ quark mass in full lattice QCD for the first time. We obtain $m_b^{\overline{\mathrm{MS}}}(m_b^{\overline{\mathrm{MS}}})=4.4(3)\mathrm{GeV}$. We are able to give physical results for the heavy quark potential parameters, $r_0=0.469(7)\mathrm{fm}$ and $r_1=0.321(5)\mathrm{fm}$. Results for the fine structure in the spectrum and the ${\rm Y}$ leptonic width are also presented. We predict the ${\rm Y}-{\eta }_b$ splitting to be 61(14) MeV, the ${{\rm Y}}^{\prime }-{\eta }_b^{\prime }$ splitting as 30(19) MeV and the splitting between the $h_b$ and the spin-average of the ${\chi }_b$ states to be less than 6 MeV. Improvements to these calculations that will be made in the near future are discussed.