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Related papers: Stout Smearing for Twisted Mass Fermions

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We present results of a first study of equation of state in finite-temperature QCD with two flavors of Wilson-type quarks. Simulations are made on lattices with temporal size $N_t=4$ and 6, using an RG-improved action for the gluon sector…

The staggered quark action on anisotropic lattices is studied. We carry out numerical simulations in the quenched approximation at three values of lattice spacing ($a_{\sigma}^{-1}=1-2$ GeV) with the anisotropy $\xi= a_{\sigma}/a_{\tau}=4$,…

High Energy Physics - Lattice · Physics 2009-11-10 Kouji Nomura , Hideo Matsufuru , Takashi Umeda

We present a first numerical study of lattice QCD with O(a) improved Wilson quarks and a chirally twisted mass term. Renormalized correlation functions are derived from the Schroedinger functional and evaluated in an intermediate space-time…

High Energy Physics - Lattice · Physics 2010-02-03 M. Della Morte , R. Frezzotti , J. Heitger , S. Sint

The nature of QCD phase transition is studied with massless up and down quarks and a light strange quark, using the Wilson formalism for quarks on a lattice with the temporal direction extension $N_t=4$. We find that the phase transition is…

High Energy Physics - Lattice · Physics 2009-10-28 Y. Iwasaki , K. Kanaya , S. Kaya , S. Sakai , T. Yoshié

We present a first Wilson twisted mass fermion calculation of the matrix element between pion states of the twist-2 operator, which is related to the the lowest moment < x > of the valence quark parton distribution function in a pion. Using…

High Energy Physics - Lattice · Physics 2009-11-11 S. Capitani , K. Jansen , M. Papinutto , A. Shindler , C. Urbach , I. Wetzorke

We show at the example of the matrix element between pion states of a twist-2, non-singlet operator that Wilson twisted mass fermions allow to compute this phenomenologically relevant quantitiy at small pseudo scalar masses of O(270 MeV).…

High Energy Physics - Lattice · Physics 2007-05-23 S. Capitani , K. Jansen , M. Papinutto , A. Shindler , I. Wetzorke , C. Urbach

We investigate the leading lattice spacing effects in mesonic two-point correlators computed with twisted mass Wilson fermions in the epsilon-regime. By generalizing the procedure already introduced for the untwisted Wilson chiral effective…

High Energy Physics - Lattice · Physics 2014-11-20 O. Bar , S. Necco , A. Shindler

Twisted mass fermions allow light quarks to be explored but with the consequence that there are mass splittings, such as between the neutral and charged pion. Using a direct calculation of the connected neutral pion correlator and…

We present the results of the recent high precision lattice calculation of the average up/down, strange and charm quark masses performed by ETMC with Nf=2 twisted mass Wilson fermions. The analysis includes data at four values of the…

High Energy Physics - Lattice · Physics 2011-04-22 B. Blossier , P. Dimopoulos , R. Frezzotti , V. Lubicz , M. Petschlies , G. C. Rossi , F. Sanfilippo , S. Simula , C. Tarantino

Using noise methods on a quenched $20^3 \times 32$ lattice at $\beta=6.0$, we have investigated vacuum expectation values and relative linear correlations among the various Wilson and twisted mass scalar and pseudoscalar disconnected loop…

High Energy Physics - Lattice · Physics 2008-11-26 Abdou Abdel-Rehim , Randy Lewis , Walter Wilcox

We report on the first master-field simulations of QCD with 2+1 dynamical quark flavours using non-perturbatively improved stabilised Wilson fermions. Our simulations are performed at a lattice spacing of 0.094 fm with 96 and 192 points in…

High Energy Physics - Lattice · Physics 2021-11-24 P. Fritzsch , J. Bulava , M. Cè , A. Francis , M. Lüscher , A. Rago

We deliver a lattice study of $\rho$ resonance parameters with p-wave $\pi\pi$ scattering phases, which are extracted by finite-size methods at one center-of-mass frame and four moving frames for six MILC lattice ensembles with pion masses…

High Energy Physics - Lattice · Physics 2016-08-29 Ziwen Fu , Lingyun Wang

The MILC collaboration's simulations with improved staggered quarks are being extended with runs at a lattice spacing of 0.06 fm with quark masses down to one tenth the strange quark mass. We give a brief introduction to these new…

High Energy Physics - Lattice · Physics 2010-11-15 C. Bernard , C. Davies , C. DeTar , Steven Gottlieb , U. M. Heller , J. E. Hetrick , L. Levkova , J. Osborn , D. B. Renner , R. Sugar , D. Toussaint

The finite-temperature chiral phase transition is investigated for three flavours of staggered quarks on a lattice of temporal extent N_t=4. In the simulation we use an improved fermion action which reduces rotational symmetry breaking of…

High Energy Physics - Lattice · Physics 2010-11-19 F. Karsch , E. Laermann , A. Peikert , B. Sturm

We investigate the use of partially twisted boundary conditions in a lattice simulation with two degenerate flavours of improved Wilson sea quarks. The use of twisted boundary conditions on a cubic volume (L^3) gives access to components of…

High Energy Physics - Lattice · Physics 2009-10-09 J. M. Flynn , A. Juttner , C. T. Sachrajda

We present results of lattice QCD simulations with mass-degenerate up and down and mass-split strange and charm (N_f = 2+1+1) dynamical quarks using Wilson twisted mass fermions at maximal twist. The tuning of the strange and charm quark…

The motivations for simulating QCD thermodynamics with Wilson fermions and a twisted mass term are introduced. The twisted mass approach provides a natural infrared cutoff and O(a) improvement at maximal twist, and can be extended to finite…

High Energy Physics - Lattice · Physics 2008-11-26 E. -M. Ilgenfritz , M. Müller-Preussker , A. Sternbeck , K. Jansen , I. Wetzorke , M. P. Lombardo , O. Philipsen

We give a determination of the phenomenological value of the Wilson (or gradient) flow scales t0 and w0 for 2+1 flavours of dynamical quarks. The simulations are performed keeping the average quark mass constant, which allows the approach…

High Energy Physics - Lattice · Physics 2015-08-25 V. G. Bornyakov , R. Horsley , R. Hudspith , Y. Nakamura , H. Perlt , D. Pleiter , P. E. L. Rakow , G. Schierholz , A. Schiller , H. Stüben , J. M. Zanotti

We present an update of our analysis [1] which includes additional ensembles at different quark masses, lattice spacings and volumes, all with high statistics. We use $N_f=2$ mass-degenerate quark flavours, employing the non-perturbatively…

We report recent efforts by CLS to generate an ensemble with physical light- and strange-quark masses in a lattice volume of 192x96^3 at $\beta=3.55$ corresponding to a lattice spacing of 0.064 fm. This ensemble is being generated as part…

High Energy Physics - Lattice · Physics 2018-04-18 Daniel Mohler , Stefan Schaefer , Jakob Simeth