English
Related papers

Related papers: Twisted mass QCD and the $\Delta I=1/2$ rule

200 papers

We present the status of a lattice calculation for the K-->pipi matrix elements of the (delta S=1) effective weak Hamiltonian, directly with two pion in the final state. We study the energy shift of two pion in a finite volume both in the…

High Energy Physics - Lattice · Physics 2012-08-27 Ph. Boucaud , V. Gimenez , C. J. D. Lin , V. Lubicz , G. Martinelli , M. Papinutto , F. Rapuano , C. T. Sachrajda , : , S. P. Qcd R. collaboration

We discuss the use of Wilson fermions with twisted mass for simulations of QCD thermodynamics. As a prerequisite for a future analysis of the finite-temperature transition making use of automatic O(a) improvement, we investigate the phase…

High Energy Physics - Lattice · Physics 2009-04-14 E. -M. Ilgenfritz , M. Müller-Preußker , M. Petschlies , K. Jansen , M. P. Lombardo , O. Philipsen , L. Zeidlewicz , A. Sternbeck

We show that maximally twisted mass fermions can be employed to regularize on the lattice the fully unquenched QCD+QED theory with vanishing $\theta$-term. We discuss how the critical mass of the up and down quarks can be conveniently…

High Energy Physics - Lattice · Physics 2016-12-08 Roberto Frezzotti , Giancarlo Rossi , Nazario Tantalo

We consider QCD with valence and sea quarks obeying different boundary conditions. We point out that the energy of low lying two hadron states do not depend on the boundary condition of the sea quarks (up to exponentially small…

High Energy Physics - Lattice · Physics 2010-04-05 Paulo F. Bedaque , Jiunn-Wei Chen

Quark bilinear operators with staple-shaped Wilson lines are used to study transverse-momentum-dependent parton distribution functions (TMDPDFs) from lattice quantum chromodynamics (QCD). Here, the renormalization factors for the isovector…

High Energy Physics - Lattice · Physics 2020-04-15 Phiala Shanahan , Michael L. Wagman , Yong Zhao

Quantum Chromodynamics on a lattice with Wilson fermions and a chirally twisted mass term for two degenerate quark flavours is considered in the framework of chiral perturbation theory. The pion masses and decay constants are calculated in…

High Energy Physics - Lattice · Physics 2010-12-23 Gernot Münster , Christian Schmidt , Enno E. Scholz

I review recent theoretical developments and numerical results of twisted mass QCD. I argue that, combined with an efficient algorithm, twisted mass QCD can be an attractive QCD lattice action, to perform large scale simulations at small…

High Energy Physics - Lattice · Physics 2007-05-23 Andrea Shindler

Lattice QCD with Wilson quarks and a chirally twisted mass term represents a promising alternative regularization of QCD, which does not suffer from unphysical fermion zero modes. We show how the correlation functions of the renormalized…

High Energy Physics - Lattice · Physics 2010-02-03 Roberto Frezzotti , Pietro Antonio Grassi , Stefan Sint , Peter Weisz

In this work we propose a method for including strong isospin breaking in twisted mass lattice calculations, while preserving flavor identification. We utilize a partially quenched construction in which the sea quarks are given by the…

High Energy Physics - Lattice · Physics 2009-04-18 Andre Walker-Loud

We present results for the masses of pseudoscalar mesons in twisted mass lattice QCD with a degenerate doublet of u and d quarks and a non-degenerate doublet of s and c quarks in the framework of next-to-leading order chiral perturbation…

High Energy Physics - Lattice · Physics 2011-05-09 Gernot Münster , Tobias Sudmann

We report on lattice QCD results for the thermodynamic equation of state of quark-gluon matter obtained with Nf=2 degenerate quark flavors. For the fermion field discretization we are using the Wilson-twisted mass prescription. Simulations…

High Energy Physics - Lattice · Physics 2015-06-23 F. Burger , E. -M. Ilgenfritz , M. P. Lombardo , M. Muller-Preussker

The possibility of imposing partially twisted boundary conditions is investigated for the scalar sector of lattice QCD. According to the commonly shared belief, the presence of quark-antiquark annihilation diagrams in the intermediate state…

High Energy Physics - Lattice · Physics 2015-06-17 Dimitri Agadjanov , Ulf-G. Meißner , Akaki Rusetsky

We present results for the nucleon structure functions and form factors obtained from 2+1 flavor lattice QCD with physical light quark masses ($m_{\pi}=135$ MeV) in a large spatial extent of about 10 fm. Our calculations are performed with…

High Energy Physics - Lattice · Physics 2022-01-03 Ryutaro Tsuji , Yasumichi Aoki , Ken-Ichi Ishikawa , Yoshinobu Kuramashi , Shoichi Sasaki , Eigo Shintani , Takeshi Yamazaki

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

For the first time, we compute non-perturbatively, i.e. without lattice perturbation theory, the renormalization constants of two-fermion operators in the quenched approximation at $\beta=6.0$, 6.2 and 6.4 using the Wilson and the…

High Energy Physics - Phenomenology · Physics 2009-10-31 V. Gimenez

We present one-loop results for the forward twist-two matrix elements relevant to the unpolarised, helicity and transversity baryon structure functions, in partially-quenched (N_f=2 and N_f=2+1) heavy baryon chiral perturbation theory. The…

High Energy Physics - Lattice · Physics 2008-11-26 William Detmold , C. -J. David Lin

We present some preliminary results for $B_K$ at $\beta=6.0$, using the twisted mass QCD formalism for the computation of bare matrix elements of the $\Delta S=2$ operator. The main advantage of the method is that mixing with other $d=6$…

High Energy Physics - Lattice · Physics 2009-11-10 P. Dimopoulos , J. Heitger , C. Pena , S. Sint , A. Vladikas

We investigate whether it is possible to extract the quark mass anomalous dimension and its scale dependence from the spectrum of the twisted mass Dirac operator in Lattice QCD. The answer to this question appears to be positive, provided…

High Energy Physics - Lattice · Physics 2014-10-08 Krzysztof Cichy

I summarize the status of the $\Delta I=1/2$ rule in $K\to\pi\pi$ decays within an {\it analytic} approach based on the dual representation of QCD as a theory of weakly interacting mesons for large $N$, where $N$ is the number of colours.…

High Energy Physics - Phenomenology · Physics 2014-10-08 Andrzej J. Buras

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