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Related papers: Universality of the Nf=2 Running Coupling

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We present an evaluation of the quark mass renormalization factor for Nf=2+1 QCD. The Schroedinger functional scheme is employed as the intermediate scheme to carry out non-perturbative running from the low energy region, where…

High Energy Physics - Lattice · Physics 2014-11-21 S. Aoki , K. -I. Ishikawa , N. Ishizuka , T. Izubuchi , K. Kanaya , Y. Kuramashi , K. Murano , Y. Namekawa , M. Okawa , Y. Taniguchi , A. Ukawa , N. Ukita , T. Yoshié

Interpreting the way that the SU(3) bare lattice coupling runs with the lattice spacing is complicated by the fact that there is a smooth cross-over region in which the strong coupling expansion transforms into a weak-coupling one. For N >…

High Energy Physics - Lattice · Physics 2008-11-26 Chris Allton , Michael Teper , Aurora Trivini

Recently, the QCD renormalization group (RG) equation at higher orders in MS-like renormalization schemes has been solved for the running coupling as a series expansion in powers of the exact 2-loop order coupling. In this work, we prove…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. A. Magradze

We investigate the renormalization group (RG) flow of SU(3) lattice gauge theory in a two coupling space with couplings $\beta_{11}$ and $\beta_{12}$ corresponding to $1\times 1$ and $1\times 2$ loops respectively. Extensive numerical…

We present the perturbative results of the discretization errors proportional to the quark mass ($\mathcal{O}(a m)$) on the QCD running coupling within lattice perturbation theory. Our analysis involves calculating the 2-loop…

High Energy Physics - Lattice · Physics 2025-12-01 Marios Costa , Demetrianos Gavriel , Haralambos Panagopoulos , Gregoris Spanoudes

The Yang-Mills gradient flow in finite volume is used to define a running coupling scheme. As our main result the discrete beta-function, or step scaling function, is calculated for scale change s=3/2 at several lattice spacings for SU(3)…

High Energy Physics - Lattice · Physics 2012-11-15 Zoltan Fodor , Kieran Holland , Julius Kuti , Daniel Nogradi , Chik Him Wong

We compute the two loop coefficient in the relation between the lattice bare coupling and the running coupling defined through the Schroedinger functional for the case of pure SU(2) gauge theory. This result is needed as one computational…

High Energy Physics - Lattice · Physics 2016-08-31 Rajamani Narayanan , Ulli Wolff

Using continuum extrapolated lattice data we trace a family of running couplings in three-flavour QCD over a large range of scales from about 4 to 128 GeV. The scale is set by the finite space time volume so that recursive finite size…

High Energy Physics - Lattice · Physics 2018-06-13 Mattia Dalla Brida , Patrick Fritzsch , Tomasz Korzec , Alberto Ramos , Stefan Sint , Rainer Sommer

We present a lattice calculation of the renormalized running coupling constant in symmetric (MOM) and asymmetric ($\widetilde{\rm MOM}$) momentum substraction schemes including $u$, $d$, $s$ and $c$ quarks in the sea. An Operator Product…

High Energy Physics - Phenomenology · Physics 2015-06-17 Ph. Boucaud , M. Brinet , F. De Soto , V. Morenas , O. Pène , K. Petrov , J. Rodríguez-Quintero

We report on the determination of the gradient flow scales in $N_f=2+1$ QCD using highly improved staggered quark (HISQ) ensembles generated by the HotQCD Collaboration for bare gauge couplings ranging from $\beta = 6.423$ to $8.400$. Using…

High Energy Physics - Lattice · Physics 2026-03-09 Rasmus Larsen , Swagato Mukherjee , Peter Petreczky , Hai-Tao Shu , Johannes Heinrich Weber

We study the scaling behaviour of the pseudo-critical couplings for the chiral phase transition in two-flavour QCD. We show that all existing results from lattice simulations on lattices with temporal extent $N_\tau = 4$, 6 and 8 can be…

High Energy Physics - Lattice · Physics 2009-10-22 Frithjof Karsch

The exact nature of the chiral phase transition in QCD is still under investigation. In $N_f=2$ and $N_f=(2+1)$ lattice simulations with staggered fermions the expected O($N$)-scaling behavior was observed. However, it is still not clear…

High Energy Physics - Phenomenology · Physics 2015-09-16 Paul Springer , Bertram Klein

We present preliminary result for the study of the renormalization group evolution of tensor bilinears in Schr\"odinger Functional (SF) schemes for $N_f=0$ and $N_f=2$ QCD with non-perturbatively $\mathcal{O}(a)$-improved Wilson fermions.…

High Energy Physics - Lattice · Physics 2015-11-26 Patrick Fritzsch , Carlos Pena , David Preti

We present a measurement of the running coupling in SU(2) with two adjoint fermions in the Yang-Mills gradient flow scheme. The simulations are performed with Schr\"odinger Functional boundary conditions using an improved HEX-smeared Wilson…

High Energy Physics - Lattice · Physics 2013-11-18 Jarno Rantaharju

The chirally rotated Schr\"odinger functional ($\chi$SF) renders the mechanism of automatic $O(a)$ improvement compatible with Schr\"odinger functional (SF) renormalization schemes. Here we define a family of renormalization schemes based…

High Energy Physics - Lattice · Physics 2016-05-31 Mattia Dalla Brida , Mauro Papinutto , Pol Vilaseca

A finite-size scaling technique is applied to the SU(2) gauge theory (without matter fields) to compute a non-perturbatively defined running coupling alpha(q) for a range of momenta q given in units of the string tension K. We find that…

High Energy Physics - Lattice · Physics 2016-08-14 Martin Lüscher , Peter Weisz , Rainer Sommer , Ulli Wolff

By (a) using an expression for the LATTICE potential of QCD in terms of a CONTINUUM running coupling and (b) globally parameterizing this coupling to interpolate between 2- (or higher-) loop QCD in the UV and the flux tube prediction in the…

High Energy Physics - Lattice · Physics 2009-10-28 Timothy R. Klassen

The scaling of the Schr"odinger functional coupling is studied numerically and perturbatively for an SU(3) lattice gauge field coupled to an O(a) improved bosonic spinor field. This corresponds to QCD with minus two light flavours and is…

High Energy Physics - Lattice · Physics 2015-06-25 Bernd Gehrmann , Juri Rolf , Stefan Kurth , Ulli Wolff

Incorporated with twisted boundary condition, Polyakov loop correlators can give a definition of the renormalized coupling. We employ this scheme for the step scaling method (with step size s = 2) in the search of conformal fixed point of…

A systematic treatment of O(a)-improvement in lattice theories with static quarks is presented. The Schr\"odinger functional is discussed and a renormalization condition for the static axial current in the SF-scheme is introduced. Its…

High Energy Physics - Lattice · Physics 2015-06-25 Martin Kurth , Rainer Sommer