English
Related papers

Related papers: QCD with dynamical Wilson fermions at $\beta=5.5$

200 papers

I report on first results of the ETMC obtained simulating lattice QCD with two degenerate flavours of Wilson twisted mass fermions, for which physical observables are automatically O(a) improved. Recent improvements of the HMC algorithm…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrea Shindler , ETM Collaboration

Measurements of the $\Lambda_b \to p \ell^- \bar{\nu}_\ell$ and $\Lambda_b \to \Lambda_c \ell^- \bar{\nu}_\ell$ decay rates can be used to determine the magnitudes of the CKM matrix elements $V_{ub}$ and $V_{cb}$, provided that the relevant…

High Energy Physics - Lattice · Physics 2015-08-05 William Detmold , Christoph Lehner , Stefan Meinel

We present results of a high statistics calculation of hadron masses and meson decay constants in the quenched approximation to lattice QCD with Wilson quarks at $\beta=$ 5.85 and 6.0 on $24^3 \times 54$ lattices. We analyze the data paying…

High Energy Physics - Lattice · Physics 2016-08-15 Y. Iwasaki , K. Kanaya , T. Yoshié , T. Hoshino , T. Shirakawa , Y. Oyanagi , S. Ichii , T. Kawai

We compare overlap fermions, which are chirally invariant, and Wilson twisted mass fermions in the approach to the chiral limit. Our quenched simulations reveal that with both formulations of lattice fermions pion masses of O(250 MeV) can…

We report on our exploratory study for the direct evaluation of the parton distribution functions from lattice QCD, based on a recently proposed new approach. We present encouraging results using Nf = 2 + 1 + 1 twisted mass fermions with a…

Results of hadron spectroscopy with two dynamical mass-degenerate chirally improved quarks are presented. Three ensembles with pion masses of 322(5), 470(4) and 525(7) MeV, lattices of size 16^3 \times 32, and lattice spacings close to 0.15…

High Energy Physics - Lattice · Physics 2011-02-18 Georg P. Engel , C. B. Lang , Markus Limmer , Daniel Mohler , Andreas Schäfer

An analysis of the pion mass and pion decay constant is performed using mixed-action Lattice QCD calculations with domain-wall valence quarks on ensembles of rooted, staggered n_f = 2+1 MILC configurations. Calculations were performed at…

High Energy Physics - Lattice · Physics 2012-11-14 S. R. Beane , W. Detmold , P. M. Junnarkar , T. C. Luu , K. Orginos , A. Parreno , M. J. Savage , A. Torok , A. Walker-Loud

We use lattice QCD to investigate the spectrum of the $\bar{b} \bar{b} u d$ four-quark system with quantum numbers $I(J^P) = 0(1^+)$. We use five different gauge-link ensembles with $2+1$ flavors of domain-wall fermions, including one at…

High Energy Physics - Lattice · Physics 2019-07-16 Luka Leskovec , Stefan Meinel , Martin Pflaumer , Marc Wagner

We study the expectation value of the phase of the fermion determinant for Wilson lattice fermions with chemical potential. We use quenched SU(3) ensembles and implement a recently proposed exact dimensional reduction of the fermion…

High Energy Physics - Lattice · Physics 2009-11-23 Julia Danzer , Christof Gattringer , Ludovit Liptak , Marina Marinkovic

We compute the static-light baryon spectrum by means of Wilson twisted mass lattice QCD using N_f = 2 flavors of sea quarks. As light u/d valence quarks we consider quarks, which have the same mass as the sea quarks with corresponding pion…

High Energy Physics - Lattice · Physics 2011-09-21 Marc Wagner , Christian Wiese

We report on numerical lattice QCD calculations of some of the low moments of the nucleon structure functions. The calculations are carried out with gauge configurations generated by the RBC and UKQCD collaborations with (2+1)-flavors of…

High Energy Physics - Lattice · Physics 2014-11-20 Yasumichi Aoki , Tom Blum , Huey-Wen Lin , Shigemi Ohta , Shoichi Sasaki , Robert Tweedie , Takeshi Yamazaki , James Zanotti

We describe two calculations involving P-wave mesons made of Wilson quarks: the strong coupling constant $\alpha_s$ in the presence of two flavors of light dynamical fermions and the mass and decay constant of the $a_1$ meson.

High Energy Physics - Lattice · Physics 2010-01-18 M. Wingate , T. DeGrand , S. Collins , U. Heller

We present a determination of the ratio of kaon and pion leptonic decay constants in isosymmetric QCD (isoQCD), $f_K / f_\pi$, making use of the gauge ensembles produced by the Extended Twisted Mass Collaboration (ETMC) with $N_f = 2 + 1 +…

We present a lattice calculation of the vector form factor of the pion for two flavours of non-perturbatively O(a) improved Wilson fermions. For the measurements we utilise the CLS ensembles which include various lattice spacings and pion…

High Energy Physics - Lattice · Physics 2011-09-02 Bastian B. Brandt , Andreas Juttner , Hartmut Wittig

We calculate mesonic two-point functions in the epsilon-regime of two-flavor QCD on the lattice with exact chiral symmetry. We use gauge configurations of size 16^3 32 at the lattice spacing a \sim 0.11 fm generated with dynamical overlap…

High Energy Physics - Lattice · Physics 2008-11-26 JLQCD Collaboration , H. Fukaya , S. Aoki , S. Hashimoto , T. Kaneko , H. Matsufuru , J. Noaki , K. Ogawa , T. Onogi , N. Yamada

Algorithmic and technical progress achieved over the last few years makes QCD simulations with light dynamical quarks much faster than before. As a result lattices with pions as light as 250--300 MeV can be simulated with the present…

High Energy Physics - Lattice · Physics 2009-04-14 Leonardo Giusti

QCD thermodynamics is considered using Wilson fermions in the fixed scale approach. The temperature dependence of the renormalized chiral condensate, quark number susceptibility and Polyakov loop is measured at four lattice spacings…

High Energy Physics - Lattice · Physics 2015-06-05 S. Borsanyi , S. Durr , Z. Fodor , C. Hoelbling , S. D. Katz , S. Krieg , D. Nogradi , B. C. Toth , N. Trombitas , K. K. Szabo

Moments of generalised parton distributions can be related to off-forward matrix elements of local operators. We calculate a few of the leading twist matrix elements for the pion on the lattice. The simulations are performed using two…

High Energy Physics - Lattice · Physics 2008-11-26 D. Brömmel , M. Diehl , M. Göckeler , Ph. Hägler , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , J. M. Zanotti

We present the current status of our lattice calculation of the electromagnetic form factor of the pion with two flavours of non-perturbatively O(a)-improved Wilson fermions. Using twisted boundary conditions and stochastic sources we…

High Energy Physics - Lattice · Physics 2013-01-17 Bastian B. Brandt , Andreas Juttner , Hartmut Wittig

We calculate the parameters describing elastic $I=1$, $P$-wave $\pi\pi$ scattering using lattice QCD with $2+1$ flavors of clover fermions. Our calculation is performed with a pion mass of $m_\pi \approx 320\:\:{\rm MeV}$ and a lattice size…