{upsilon} spectrum and m{sub b} from full lattice QCD

Journal Article · Tue Nov 01 04:00:00 EST 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.72.094507· OSTI ID:20713855

Gray, A; Gulez, E; Shigemitsu, J ^[1]; Allison, I; Davies, C T.H. ^[2]; Lepage, G P ^[3]; Wingate, M ^[4]

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1. Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States)
2. Department of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom)
3. Laboratory of Elementary-Particle Physics, Cornell University, Ithaca, New York 14853 (United States)
4. Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195 (United States)

We show results for the {upsilon} 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 {upsilon} 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 {upsilon} 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{sub b}{sup MS}(m{sub b}{sup MS})=4.4(3) GeV. We are able to give physical results for the heavy quark potential parameters, r{sub 0}=0.469(7) fm and r{sub 1}=0.321(5) fm. Results for the fine structure in the spectrum and the {upsilon} leptonic width are also presented. We predict the {upsilon}-{eta}{sub b} splitting to be 61(14) MeV, the {upsilon}{sup '}-{eta}{sub b}{sup '} splitting as 30(19) MeV and the splitting between the h{sub b} and the spin-average of the {chi}{sub b} states to be less than 6 MeV. Improvements to these calculations that will be made in the near future are discussed.

• OSTI ID: 20713855
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 9 Vol. 72; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
B QUARKS
C QUARKS
COMPARATIVE EVALUATIONS
D QUARKS
FINE STRUCTURE
GEV RANGE
GLUONS
LATTICE FIELD THEORY
MESON SPECTROSCOPY
MEV RANGE
PARTICLE WIDTHS
POTENTIALS
QUANTUM CHROMODYNAMICS
RESONANCE PARTICLES
REST MASS
S QUARKS
SPIN
UPSILON-10355 MESONS
UPSILON-10580 MESONS
UPSILON-9460 MESONS
VACUUM POLARIZATION