J. O. Daldrop

Publications (2)7.37 Total impact

• Source

  Available from: ArXiv

  Article: Prediction of the bottomonium D-wave spectrum from full lattice QCD.

  J O Daldrop, C T H Davies, R J Dowdall
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  ABSTRACT: We calculate the full spectrum of D-wave states in the Υ system in lattice QCD for the first time, by using an improved version of nonrelativistic QCD on coarse and fine "second-generation" gluon field configurations from the MILC Collaboration that include the effect of up, down, strange, and charm quarks in the sea. By taking the 2S-1S splitting to set the lattice spacing, we determine the (3)D2-1S splitting to 2.3% and find agreement with experiment. Our prediction of the fine structure relative to the (3)D2 gives the (3)D3 at 10.181(5) GeV and the (3)D1 at 10.147(6) GeV. We also discuss the overlap of (3)D1 operators with (3)S1 states.
  Physical Review Letters 03/2012; 108(10):102003. · 7.37 Impact Factor
• Source

  Available from: Ronald Horgan

  Article: The Upsilon spectrum and the determination of the lattice spacing from lattice QCD including charm quarks in the sea

  R. J. Dowdall, B. Colquhoun, J. O. Daldrop, C. T. H. Davies, I. D. Kendall, E. Follana, T. C. Hammant, R. R. Horgan, G. P. Lepage, C. J. Monahan, E. H. Müller
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  ABSTRACT: We give results for the Upsilon spectrum from lattice QCD using an improved version of the NRQCD action for b quarks which includes radiative corrections to kinetic terms at O(v^4) in the velocity expansion. We also include for the first time the effect of up, down, strange and charm quarks in the sea using 'second generation' gluon field configurations from the MILC collaboration. Using the {\Upsilon} 2S - 1S splitting to determine the lattice spacing, we are able to obtain the 1P - 1S splitting to 1.4% and the 3S - 1S splitting to 2.4%. Our improved result for M (Upsilon) - M (eta_b) is 70(9) MeV and we predict M(Upsilon) - M(eta_b') = 35(3) MeV. We also calculate pi, K and eta_s correlators using the Highly Improved Staggered Quark action and perform a chiral and continuum extrapolation to give values for M(eta_s) (0.6893(12) GeV) and f_{eta_s} (0.1819(5) GeV) that allow us to tune the strange quark mass as well as providing an independent and consistent determination of the lattice spacing. Combining the NRQCD and HISQ analyses gives mb/ms = 54.7(2.5) and a value for the heavy quark potential parameter of r_1 = 0.3209(26) fm.
  10/2011;