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Related papers: Schr"odinger functional at negative flavour number

200 papers

We present a scaling study of lattice QCD with O(a) improved Wilson fermions and a chirally twisted mass term. In order to get precise results with a moderate computational effort, we have considered a system of physical size of 0.75^3 *…

High Energy Physics - Lattice · Physics 2009-10-31 M. Della Morte , R. Frezzotti , J. Heitger , S. Sint

We present a measurement of the Schr\"odinger Functional running coupling in SU(2) lattice gauge theory with adjoint fermions. We use HEX smearing and clover improvement to reduce the discretization effects. We obtain a robust continuum…

High Energy Physics - Lattice · Physics 2017-08-23 Jarno Rantaharju , Kari Rummukainen , Kimmo Tuominen

We study the evolution of the coupling in SU(2) gauge field theory with $N_f=4$, 6 and 10 fundamental fermion flavours on the lattice. These values are chosen close to the expected edges of the conformal window, where the theory possesses…

High Energy Physics - Lattice · Physics 2015-03-19 Tuomas Karavirta , Jarno Rantaharju , Kari Rummukainen , Kimmo Tuominen

We discuss the Schr\"odinger functional in lattice QCD with staggered fermions including its order $O(a)$ boundary counterterms. We relate it, in the classical continuum limit, to the Schr\"odinger functional as obtained in the same limit…

High Energy Physics - Lattice · Physics 2009-10-30 Urs M. Heller

We report on a scaling test of several mesonic observables in the non-perturbatively O(a) improved Wilson theory with two flavors of dynamical quarks. The observables are constructed in a fixed volume of 2.4fm x (1.8fm)^3 with Schroedinger…

High Energy Physics - Lattice · Physics 2008-11-26 Michele Della Morte , Patrick Fritzsch , Harvey B. Meyer , Hubert Simma , Rainer Sommer , Shinji Takeda , Oliver Witzel , Ulli Wolff

The two loop coefficient of the expansion of the Schroedinger functional coupling in terms of the lattice coupling is calculated for the SU(3) Yang-Mills theory. This coefficient is required to relate lattice data to the MS-bar-coupling. As…

High Energy Physics - Lattice · Physics 2009-10-30 Achim Bode

Walking technicolor theory attempts to realize electroweak symmetry breaking as the spontaneous chiral symmetry breakdown caused by the gauge dynamics with slowly varying gauge coupling constant and large mass anomalous dimension.…

High Energy Physics - Lattice · Physics 2011-05-12 M. Hayakawa , K. -I. Ishikawa , Y. Osaki , S. Takeda , S. Uno , N. Yamada

We numerically study QCD with a single quark flavour on the lattice probing predictions from effective field theories that are equivalent to minimal super-symmetric Yang-Mills theory in the large $N_c$ limit. The hadronic spectrum including…

High Energy Physics - Lattice · Physics 2021-11-25 Michele Della Morte , Benjamin Jäger , Francesco Sannino , J. Tobias Tsang , Felix P. G. Ziegler

We complete a program of study of SU(N) gauge theories coupled to two flavors of fermions in the two-index symmetric representation by performing numerical simulations in SU(4). The beta function, defined and calculated via the…

High Energy Physics - Lattice · Physics 2013-05-30 Thomas DeGrand , Yigal Shamir , Benjamin Svetitsky

We determine O($a$) boundary improvement coefficients up to 1-loop level for the Schr\"odinger Functional coupling with improved gauge actions including plaquette and rectangle loops. These coefficients are required to implement 1-loop…

High Energy Physics - Lattice · Physics 2009-11-10 Shinji Takeda , Sinya Aoki , Kiyotomo Ide

The standard method to calculate non-perturbatively the evolution of the running coupling of a SU(N) gauge theory is based on the Schr\"odinger functional (SF). In this paper we construct a family of boundary fields for general values of N…

High Energy Physics - Lattice · Physics 2015-06-22 Ari Hietanen , Tuomas Karavirta , Pol Vilaseca

We present the scale setting for a new set of gauge configurations generated with $N_f=3+1$ Wilson quarks with a non-perturbatively determined clover coefficient in a massive O($a$) improvement scheme. The three light quarks are degenerate,…

High Energy Physics - Lattice · Physics 2020-05-20 Roman Höllwieser , Francesco Knechtli , Tomasz Korzec

We study the SU(3) gauge theory with Nf=12 flavors in the fundamental representation by use of lattice simulations with staggered fermions. With a non-improved action we observe a chiral zero-temperature (bulk) transition separating a…

High Energy Physics - Lattice · Physics 2013-03-26 Albert Deuzeman , Maria Paola Lombardo , Tiago Nunes da Silva , Elisabetta Pallante

We have measured the running coupling constant of SU(3) gauge theory coupled to Nf=2 flavors of symmetric representation fermions, using the Schrodinger functional scheme. Our lattice action is defined with hypercubic smeared links which,…

High Energy Physics - Lattice · Physics 2014-11-21 Thomas DeGrand , Yigal Shamir , Benjamin Svetitsky

SU(2) gauge theory with two fermions transforming under the adjoint representation may appear conformal or almost conformal in the infrared, and is one of the candidate theories for building models for technicolor. Early lattice Monte Carlo…

High Energy Physics - Lattice · Physics 2015-05-20 Tuomas Karavirta , Anne Mykkanen , Jarno Rantaharju , Kari Rummukainen , Kimmo Tuominen

We present preliminary results on the lattice simulation of an SU(2) gauge theory with two fermion flavors and one strongly interacting scalar field, all in the fundamental representation of SU(2). The motivation for this study comes from…

High Energy Physics - Lattice · Physics 2018-04-18 Martin Hansen , Tadeusz Janowski , Claudio Pica , Arianna Toniato

The LatKMI collaboration is studying systematically the dynamical properties of N_f = 4,8,12,16 SU(3) gauge theories using lattice simulations with (HISQ) staggered fermions. Exploring the spectrum of many-flavour QCD, and its scaling near…

We review our new strategy and current status towards a high precision computation of the Lambda parameter from three-flavour simulations in QCD. To reach this goal we combine specific advantages of the Schr\"odinger functional and gradient…

High Energy Physics - Lattice · Physics 2014-12-01 M. Dalla Brida , P. Fritzsch , T. Korzec , A. Ramos , S. Sint , R. Sommer

Existing non-perturbative computations of the running coupling of quenched QCD in the Schroedinger functional scheme are extended to scales mu lying much deeper in the low-energy regime. We are able to reach 1/mu ~ 0.9 fm, where a…

High Energy Physics - Lattice · Physics 2015-06-25 Jochen Heitger , Hubert Simma , Rainer Sommer , Ulli Wolff

Based on simulations of 2+1 flavor lattice QCD with M\"obius domain wall fermions at high temperatures, we compute a series of spatial correlation functions to study the screening masses in mesonic states. We compare these masses with the…

High Energy Physics - Lattice · Physics 2024-01-25 David Ward , Sinya Aoki , Yasumichi Aoki , Hidenori Fukaya , Shoji Hashimoto , Issaku Kanamori , Takashi Kaneko , Jishnu Goswami , Yu Zhang