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Related papers: Computation of $\bar{\Lambda}$ and $\lambda_1$ wit…

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The heavy-quark expansion for inclusive semi-leptonic B decays introduces $\bar{\Lambda}$ and $\lambda_1$, which are matrix elements in heavy-quark effective field theory. We review how they can be obtained from an analysis of the heavy…

High Energy Physics - Lattice · Physics 2019-08-14 Elizabeth D. Freeland , Andreas S. Kronfeld , James N. Simone , Ruth S. Van de Water

Using a specific scheme of the QCD sum rules for heavy quarkonium in the leading approximation over the inverse heavy quark mass, one gets the estimate of the difference between the masses of the heavy meson and heavy quark $\bar \Lambda =…

High Energy Physics - Phenomenology · Physics 2008-02-03 V. V. Kiselev

QCD inequalities are derived for the masses of mesons and baryons containing a single heavy quark using the heavy quark effective field theory. A rigorous lower bound is obtained for the $\bar\Lambda$ parameters of the heavy quark effective…

High Energy Physics - Phenomenology · Physics 2011-01-25 Zachary Guralnik , Aneesh V. Manohar

I discuss old and new determinations of the light quark masses using lattice QCD. Most lattice results using various approximations can be fit together in a simple picture which is consistent with lower values than conventionally supposed:…

High Energy Physics - Phenomenology · Physics 2011-02-01 Paul B. Mackenzie

We present a determination of the QCD parameter Lambda in the quenched approximation (n_f=0) and for two flavours (n_f=2) of light dynamical quarks. The calculations are performed on the lattice using O(a) improved Wilson fermions and…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Göckeler , R. Horsley , A. C. Irving , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben

We explain how scale dependent renormalized quantities can be computed using lattice QCD. Two examples are used: the running coupling and quark masses. A reliable computation of the $\Lambda$-parameter in the quenched approximation is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Rainer Sommer

We compute charm and bottom quark masses in the quenched approximation and in the continuum limit of lattice QCD. We make use of a step scaling method, previously introduced to deal with two scale problems, that allows to take the continuum…

High Energy Physics - Lattice · Physics 2016-09-01 G. M. de Divitiis , M. Guagnelli , F. Palombi , R. Petronzio , N. Tantalo

We apply heavy-quark effective theory to separate long- and short-distance effects of heavy quarks in lattice gauge theory. In this approach, the inverse heavy-quark mass and the lattice spacing are treated as short distances, and their…

High Energy Physics - Lattice · Physics 2014-11-17 Junpei Harada , Shoji Hashimoto , Ken-Ichi Ishikawa , Andreas S. Kronfeld , Tetsuya Onogi , Norikazu 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

Combining the experimental data on the inclusive decays $D\to X\,e\,\nu$, $B\to X\,e\,\nu$ and $B\to X\,\tau\,\nu$, we find severe constraints on the $\bar\Lambda$ and $\lambda_1$ parameters of the Heavy Quark Effective Theory. In…

High Energy Physics - Phenomenology · Physics 2009-12-30 Zoltan Ligeti , Yosef Nir

We determine $\Lambda_{\bar{\textrm{MS}}}^{(n_f=2)}$ by fitting perturbative expressions for the quark-antiquark static potential to lattice results for QCD with $n_f=2$ dynamical quark flavors. To this end we use the perturbative static…

High Energy Physics - Phenomenology · Physics 2014-10-01 Felix Karbstein , Antje Peters , Marc Wagner

We compare the perturbatively calculated QCD potential to that obtained from lattice calculations in the theory without light quark flavours. We examine E_tot(r) = 2 m_pole + V_QCD(r) by re-expressing it in the MSbar mass m =…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Recksiegel , Y. Sumino

Existing lattice data on the QCD phase transition are analyzed in renormalized perturbation theory. In quenched QCD it is found that T_c scales for lattices with only 3 time slices, and that T_c/Lambda_msbar=1.15 \pm 0.05. A preliminary…

High Energy Physics - Lattice · Physics 2009-10-31 Sourendu Gupta

We investigate the masses of the light quarks with lattice QCD. We show that most of the large dependence on the lattice spacing, a, observed in previous determinations using Wilson fermions is removed with the use of an O(a) corrected…

We compute the strange and the average up/down quark masses in the quenched approximation of lattice QCD, by using the O(a)-improved Wilson action and operators and by implementing the non-perturbative renormalization. Our computation is…

High Energy Physics - Lattice · Physics 2008-11-26 Damir Becirevic , Vittorio Lubicz , Cecilia Tarantino

I discuss the results of a new calculation of the charm and bottom quark masses in the quenched approximation and in the continuum limit of lattice QCD. The work has been done by the APE group at the ``Tor Vergata'' University making use of…

High Energy Physics - Lattice · Physics 2009-11-10 Nazario Tantalo

We study effective energies of heavy-light meson correlation functions in lattice QCD and a small volume of (0.2 fm)^4 to non-perturbatively calculate their dependence on the heavy quark mass in the continuum limit. Our quenched results…

High Energy Physics - Lattice · Physics 2009-11-10 Jochen Heitger , Jan Wennekers

We study on the lattice the correlator of heavy-quark currents in the vicinity of vanishing momentum. The renormalized charmed quark mass, the renormalized strong coupling constant and gluon condensate can be defined in terms of the…

High Energy Physics - Lattice · Physics 2009-10-28 A. Bochkarev , Ph. de Forcrand

The mass parameter of orbitally excited $\Lambda_c$ baryons is calculated by using QCD sum rule in the framework of heavy quark effective theory. Two kinds of interpolating current for the excited heavy baryons are introduced. It is…

High Energy Physics - Phenomenology · Physics 2009-10-31 Jong-Phil Lee , Chun Liu , H. S. Song

We perform a lattice study of heavy baryons, containing one ($\Lambda_b$) or two $b$-quarks ($\Xi_b$). Using the quenched approximation we obtain for the mass of $\Lambda_b$ $$ M_{\Lambda_b}= 5.728 \pm 0.144 \pm 0.018 {\rm GeV}.$$ The mass…

High Energy Physics - Lattice · Physics 2019-08-17 C. Alexandrou , A. Borrelli , S. Güsken , F. Jegerlehner , K. Schilling , G. Siegert , R. Sommer
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