English
Related papers

Related papers: Alpha_S from Upsilon Spectroscopy with Dynamical W…

200 papers

We estimate the strong coupling constant from the perturbative expansion of the plaquette. The scale is set by the 2S-1S and 1P-1S splittings in bottomonium which are computed in NRQCD on dynamical gauge configurations with nf=2 degenerate…

High Energy Physics - Lattice · Physics 2009-10-31 SESAM Collaboration , A. Spitz , N. Eicker , S. Guesken , H. Hoeber , P. Lacock , T. Lippert , K. Schilling , T. Struckmann , P. Ueberholz , J. Viehoff

We describe the first lattice determination of the strong coupling constant with 3 flavors of dynamical quarks. The method follows previous analyses in using a perturbative expansion for the plaquette and Upsilon spectroscopy to set the…

High Energy Physics - Lattice · Physics 2015-06-25 C. Davies , A. Gray , M. Alford , E. Follana , J. Hein , P. Lepage , Q. Mason , M. Nobes , J. Shigemit su , H. Trottier , M. Wingate

We use lattice QCD simulations, with MILC configurations (including vacuum polarization from u, d, and s quarks), to update our previous determinations of the QCD coupling constant. Our new analysis uses results from 6 different lattice…

High Energy Physics - Lattice · Physics 2009-01-08 C. T. H. Davies , K. Hornbostel , I. D. Kendall , G. P. Lepage , C. McNeile , J. Shigemitsu , H. Trottier

We present a determination of the QCD coupling constant, $\alpha_s$, obtained by fitting lattice results for the flavour $ud$ hadronic vacuum polarisation function to continuum perturbation theory. We use $n_f=2+1$ flavours of Domain Wall…

High Energy Physics - Lattice · Physics 2018-07-09 Renwick J. Hudspith , Randy Lewis , Kim Maltman , Eigo Shintani

Comparing perturbative calculations with a lattice computation of the static energy in quantum chromodynamics at short distances, we obtain a determination of the strong coupling alpha_s. Our determination is performed at a scale of around…

High Energy Physics - Phenomenology · Physics 2012-08-27 Xavier Garcia i Tormo

We present a new determination of the QCD strong coupling constant based on precise lattice calculations of the $\Upsilon$ spectrum. The largest systematic uncertainty in previous such determinations resulted from the absence of vacuum…

High Energy Physics - Phenomenology · Physics 2009-10-28 C. T. H. Davies , K. Hornbostel , G. P. Lepage , A. Lidsey , J. Shigemitsu , J. Sloan

We determine the strong coupling constant $\alpha_s$ from the static QCD potential by matching a theoretical calculation with a lattice QCD computation. We employ a new theoretical formulation based on the operator product expansion, in…

High Energy Physics - Phenomenology · Physics 2019-05-02 Hiromasa Takaura , Takashi Kaneko , Yuichiro Kiyo , Yukinari Sumino

We compare lattice data for the short-distance part of the static energy in 2+1 flavor quantum chromodynamics (QCD) with perturbative calculations, up to next-to-next-to-next-to leading-logarithmic accuracy. We show that perturbation theory…

High Energy Physics - Phenomenology · Physics 2013-05-30 Alexei Bazavov , Nora Brambilla , Xavier Garcia i Tormo , Peter Petreczky , Joan Soto , Antonio Vairo

We present a new determination of the strong coupling constant from lattice QCD simulations. We use four different short-distance quantities to obtain the coupling, three different (infrared) meson splittings to tune the simulation…

High Energy Physics - Lattice · Physics 2016-08-24 C. T. H. Davies , K. Hornbostel , G. P. Lepage , P. McCallum , J. Shigemitsu , J. Sloan

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…

Recently, realistic lattice QCD calculations with 2+1 flavors of domain wall fermions and the Iwasaki gauge action have been performed by the RBC and UKQCD collaborations. Here, results for the bottomonium spectrum computed on their gauge…

High Energy Physics - Lattice · Physics 2009-05-01 Stefan Meinel

We determine the strong coupling constant $\alpha_s$ from a lattice calculation of vacuum polarization functions (VPF) in three-flavor QCD with dynamical overlap fermions. Fitting lattice data of VPF to the continuum perturbative formula…

High Energy Physics - Lattice · Physics 2014-09-05 E. Shintani , S. Aoki , H. Fukaya , S. Hashimoto , T. Kaneko , T. Onogi , N. Yamada

We obtain a new value for the QCD coupling constant by combining lattice QCD simulations with experimental data for hadron masses. Our lattice analysis is the first to: 1) include vacuum polarization effects from all three light-quark…

High Energy Physics - Lattice · Physics 2009-11-11 Q. Mason , H. D. Trottier , C. T. H. Davies , K. Foley , A. Gray , G. P. Lepage , M. Nobes , J. Shigemitsu

We determine the strong coupling constant $\alpha_s(M_Z)$ from the static QCD potential by matching a lattice result and a theoretical calculation. We use a new theoretical framework based on operator product expansion (OPE), where…

High Energy Physics - Phenomenology · Physics 2019-05-24 Hiromasa Takaura , Takashi Kaneko , Yuichiro Kiyo , Yukinari Sumino

We present an overview of the recent lattice determination of the QCD coupling $\alpha_s$ by the ALPHA Collaboration. The computation is based on the non-perturbative determination of the $\Lambda$-parameter of $N_{\rm f}=3$ QCD, and the…

High Energy Physics - Phenomenology · Physics 2018-12-18 Mattia Dalla Brida

The measurement of the eta_b mass, together with a QCD result for the hyperfine splitting E_{HFS}=M_{Upsilon(1S)}-M_{eta_b}, allows us to determine the strong coupling constant alpha_s at a low energy scale. The result…

High Energy Physics - Phenomenology · Physics 2011-02-25 Pietro Colangelo , Pietro Santorelli , Egidio Scrimieri

We calculate the full spectrum of D-wave states in the Upsilon system in lattice QCD for the first time, using an improved version of NonRelativistic QCD on coarse and fine "second generation" gluon field configurations from the MILC…

High Energy Physics - Lattice · Physics 2015-06-03 J. O. Daldrop , C. T. H. Davies , R. J. Dowdall

We present new results on $\Upsilon$ and $J/\Psi$ spectroscopy using Lattice NRQCD. Charmonium results at quenched $\beta$ = 5.7 show agreement with experiment within understood systematic errors. We compare bottomonium results at quenched…

High Energy Physics - Lattice · Physics 2019-08-21 NRQCD collaboration

We present data for the scaling behavior of lattice QCD with two flavors of light Wilson fermions. This is done by matching $\pi$ n and $\rho$ masses at the two lattice sizes of $16^3\times32 $ and $8^3\times16$. We find that at…

High Energy Physics - Lattice · Physics 2009-10-28 K. M. Bitar , R. G. Edwards , U. M. Heller , A. D. Kennedy , P. Vranas

The static energy is an excellent observable for extracting the strong coupling $\alpha_s$ on the lattice. For short distances, the static energy can be calculated both on the lattice using Wilson line correlators, and with perturbation…

‹ Prev 1 2 3 10 Next ›