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Related papers: Chiral condensate from the twisted mass Dirac oper…

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A numerical investigation of the quenched Schwinger model on the lattice using the overlap Dirac operator points to a divergent chiral condensate.

High Energy Physics - Lattice · Physics 2009-10-31 Joe Kiskis , Rajamani Narayanan

We report on our ongoing project of determining the chiral condensate of two-flavor QCD from the Banks-Casher relation. We compute the mode number of the O(a)-improved Wilson-Dirac operator for several values of \Lambda, and we discuss…

High Energy Physics - Lattice · Physics 2013-09-19 Georg P. Engel , Leonardo Giusti , Stefano Lottini , Rainer Sommer

We study the scalar condensate and the topological susceptibility for a continuous range of quark masses in the Schwinger model with $N_f=0,1,2$ dynamical flavors, using both the overlap and the staggered discretization. At finite lattice…

High Energy Physics - Lattice · Physics 2008-11-26 Stephan Dürr , Christian Hoelbling

We present precision lattice calculations of the pseudoscalar decay constants of the charmed sector as well as determinations of the bottom quark mass and its ratio to the charm quark mass. We employ Nf=2+1+1 dynamical quark gauge…

High Energy Physics - Lattice · Physics 2014-11-04 A. Bussone , N. Carrasco , P. Dimopoulos , R. Frezzotti , P. Lami , V. Lubicz , F. Nazzaro , E. Picca , L. Riggio , G. C. Rossi , F. Sanfilippo , S. Simula , C. Tarantino

We determine the strange quark condensate from lattice QCD for the first time and compare its value to that of the light quark and chiral condensates. The results come from a direct calculation of the expectation value of the trace of the…

High Energy Physics - Lattice · Physics 2013-03-14 C. McNeile , A. Bazavov , C. T. H. Davies , R. J. Dowdall , K. Hornbostel , G. P. Lepage , H. D. Trottier

The finite temperature chiral condensate for 2+1 quark flavors is considered in the framework of the hadron resonance gas model. This requires some dynamical information, for which two models are employed: one based on the quark structure…

High Energy Physics - Phenomenology · Physics 2013-06-05 J. Jankowski , D. Blaschke , M. Spalinski

We study the heavy baryon mass spectrum on gauge configurations that include 2+1 flavors of dynamical improved staggered quarks. A valence clover heavy quark is combined with two improved staggered light quark propagators to form baryons…

High Energy Physics - Lattice · Physics 2008-11-26 Heechang Na , Steven Gottlieb

I extend to QCD an efficient method for lattice gauge theory with dynamical fermions. Once the eigenvalues of the Dirac operator and the density of states of pure gluonic configurations at a set of plaquette energies (proportional to the…

High Energy Physics - Lattice · Physics 2009-11-07 Xiang-Qian Luo

We study lattice QCD determinations of the pion mass and decay constant by means of chiral perturbation theory (ChPT). The lattice data are obtained from large scale simulations with N_f=2 flavours of twisted mass fermions at maximal twist.…

High Energy Physics - Phenomenology · Physics 2019-08-13 P. Dimopoulos , R. Frezzotti , G. Herdoiza , K. Jansen , C. Michael , C. Urbach

We present results on the masses of the low-lying baryons using ten ensembles of gauge configurations with $N_f =2+1+1$ dynamical twisted mass fermions, at three values of the lattice spacing, spanning a pion mass range from about 210 MeV…

High Energy Physics - Lattice · Physics 2014-12-03 C. Alexandrou , V. Drach , K. Hadjiyiannakou , K. Jansen , C. Kallidonis , G. Koutsou

We review recent results for the chiral behavior of meson masses and decay constants and the determination of the light quark masses by the RBC and UKQCD collaborations. We find that one-loop SU(2) chiral perturbation theory represents the…

High Energy Physics - Lattice · Physics 2010-01-21 Enno E. Scholz

We present first results on the octet and decuplet strange baryon spectrum with $N_f=2+1+1$ twisted mass quarks. We use an Osterwalder Seiler valence strange quark with a mass tuned to the kaon and compare the results with those obtained in…

High Energy Physics - Lattice · Physics 2010-12-20 Vincent Drach , Karl Jansen , Jaume Carbonell , Mauro Papinutto , Constantia Alexandrou

We present results from an ongoing computation of masses of $D$ mesons, $D_s$ mesons and charmonium, including both ground states and several parity and angular momentum excitations. We employ 2+1+1 flavours of dynamical maximally twisted…

High Energy Physics - Lattice · Physics 2015-10-28 Krzysztof Cichy , Martin Kalinowski , Marc Wagner

We study the spectrum of the QCD Dirac operator for two colors with fermions in the fundamental representation and for two or more colors with adjoint fermions. For $N_f$ flavors, the chiral flavor symmetry of these theories is…

High Energy Physics - Theory · Physics 2009-10-31 D. Toublan , J. J. M. Verbaarschot

We present first results of a mixed action project. We analyze gauge configurations generated with two flavors of dynamical twisted mass fermions. Neuberger's overlap Dirac operator is used for the valence sector. The various choices in the…

High Energy Physics - Lattice · Physics 2008-11-26 O. Bar , K. Jansen , S. Schaefer , L. Scorzato , A. Shindler

We present a lattice QCD determination of the average up-down, strange and charm quark masses based on simulations performed by the European Twisted Mass Collaboration with $N_f = 2 + 1 + 1$ dynamical fermions. We simulated at three…

High Energy Physics - Lattice · Physics 2014-10-06 N. Carrasco , P. Dimopoulos , R. Frezzotti , P. Lami , V. Lubicz , D. Palao , E. Picca , L. Riggio , G. C. Rossi , F. Sanfilippo , S. Simula , C. Tarantino

We measure the low lying eigenmodes of an overlap Dirac operator on 2--flavor staggered configurations. By comparing the eigenmode distribution to the predictions of Random Matrix Theory we test to what accuracy staggered configurations…

High Energy Physics - Lattice · Physics 2008-11-26 Anna Hasenfratz , Roland Hoffmann

We apply the probability distribution function method to the study of chiral properties of QCD with quarks in the exact massless limit. A relation among the chiral condensate, zeros of the Bessel function and eigenvalue of Dirac operator is…

High Energy Physics - Lattice · Physics 2009-10-02 Xiang-Qian Luo

We compute the low lying eigenvalues of the Hermitian Dirac operator in lattice QCD with $N_{\rm f} = 2+1+1$ twisted mass fermions. We discuss whether these eigenvalues are in the $\epsilon$-regime or the $p$-regime of Wilson chiral…

High Energy Physics - Lattice · Physics 2018-11-29 Krzysztof Cichy , Savvas Zafeiropoulos

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