title: Mass of the eta b and alpha s from the nonrelativistic renormalization group.
abstract: We sum up the next-to-leading logarithmic corrections to the heavy-quarkonium hyperfine splitting, using the nonrelativistic renormalization group. On the basis of this result, we predict the mass of the eta(b) meson to be M(eta(b))=9421+/-11(th)+9-8(delta alpha(s)) MeV. The experimental measurement of M(eta(b)) with a few MeV error would be sufficient to determine alpha(s)(M(Z)) with an accuracy of +/-0.003. For the hyperfine splitting in charmonium, the use of the nonrelativistic renormalization group brings the perturbative prediction significantly closer to the experimental figure.
authors.affiliation: II. Institut für Theoretische Physik, Universität Hamburg, 22761 Hamburg, Germany.
authors.forename: Bernd A
authors.initials: BA
authors.lastname: Kniehl
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Penin
authors.forename: Antonio
authors.initials: A
authors.lastname: Pineda
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Smirnov
authors.forename: Matthias
authors.initials: M
authors.lastname: Steinhauser