Bottomonium precision tests from full lattice QCD: Hyperfine splitting, Υ leptonic width, and b quark contribution to e+e− → hadrons

We calculate the mass difference between the \ud Υ\ud and \ud η\ud b\ud and the \ud Υ\ud leptonic width from lattice QCD using the Highly Improved Staggered Quark formalism for the \ud b\ud quark and including \ud u\ud , \ud d\ud , \ud s\ud and \ud c\ud quarks in the sea. We have results for lattices with lattice spacing as low as 0.03 fm and multiple heavy quark masses, enabling us to map out the heavy quark mass dependence and determine values at the \ud b\ud quark mass. Our results are: \ud M\ud Υ\ud −\ud M\ud η\ud b\ud =\ud 57.5\ud (\ud 2.3\ud )\ud (\ud 1.0\ud )\ud M\ud e\ud V\ud (where the second uncertainty comes from neglect of quark-line disconnected correlation functions) and decay…