English
Related papers

Related papers: Exact calculation of disconnected loops

200 papers

A full, high-statistic I=0 and I=2 $\pi-\pi$ scattering calculation including the disconnected diagram is performed on 2+1 flavor, domain wall fermion gauge configurations generated using the Iwasaki gauge action with $\beta=2.13$, a…

High Energy Physics - Lattice · Physics 2010-11-05 Qi Liu

A comparison of the noise variance between algorithms for calculating disconnected loop signals in lattice QCD is carried out. The methods considered are the Z(N) noise method and the Volume method. We find that the noise variance is…

High Energy Physics - Lattice · Physics 2009-10-30 Walter Wilcox , Bruce Lindsay

Disconnected diagrams are expected to be sensitive to the inclusion of dynamical fermions. We present a feasibility study for the observation of such effects on the nucleonic matrix elements of the axial vector current, using SESAM full QCD…

High Energy Physics - Lattice · Physics 2009-10-30 J. Viehoff , N. Eicker , S. Guesken , H. Hoeber , P. Lacock , Th. Lippert , G. Ritzenhoefer , K. Schilling , A. Spitz , P. Ueberholz

We calculate connected and disconnected contributions to the flavour singlet scalar density amplitude of the nucleon in a full QCD lattice simulation with $n_f=2$ dynamical Wilson fermions at $\beta=5.6$ on a $16^3 \times 32$ lattice. We…

High Energy Physics - Lattice · Physics 2012-08-27 SESAM-Collaboration , : , S. Güsken , P. Ueberholz , J. Viehoff , N. Eicker , P. Lacock , T. Lippert , K. Schilling , A. Spitz , Th. Struckmann

Stochastic noise estimator method is a powerful tool to calculate the disconnected insertion involving quark loops. We study the variance reduction technique with unbiased subtraction. We use the complex $Z_2$ noise to calculate the quark…

High Energy Physics - Lattice · Physics 2009-11-07 Nilmani Mathur , Shao-Jing Dong

We report lattice results of $D_s$ meson semi-leptonic decay form factors to $\eta$ and $\eta'$ mesons. This decay process contains disconnected fermion loops, which are challenging in lattice calculations. Our result shows that the…

High Energy Physics - Lattice · Physics 2013-12-02 Sara Collins , Issaku Kanamori , Johannes Najjar

Lattice spin models are useful for studying critical phenomena and allow the extraction of equilibrium and dynamical properties. Simulations of such systems are usually based on Monte Carlo (MC) techniques, and the main difficulty is often…

Computational Physics · Physics 2012-09-13 Tal Levy , Guy Cohen , Eran Rabani

We investigate the electromagnetic mass splittings in the pseudoscalar meson and nucleon systems by combining 2+1 flavor domain wall fermion gauge configurations, generated by the RBC and UKQCD collaborations, and quenched, non-compact,…

High Energy Physics - Lattice · Physics 2010-01-21 Ran Zhou , Thomas Blum , Takumi Doi , Masashi Hayakawa , Taku Izubuchi , Norikazu Yamada

We study the flavour breaking effects appearing in the Wilson twisted mass formulation of lattice QCD. In this quenched study, we focus on the mass splitting between the neutral and the charged pion, determining the neutral pion mass with a…

High Energy Physics - Lattice · Physics 2008-11-26 K. Jansen , C. McNeile , C. Michael , K. Nagai , M. Papinutto , J. Pickavance , A. Shindler , C. Urbach , I. Wetzorke

In this article we describe our studies of the sigma meson, f_0(500), using two-pion correlation functions. We use lattice quantum chromodynamics in the quenched approximation with so-called clover fermions. By working at unphysical pion…

High Energy Physics - Lattice · Physics 2017-08-23 Dean Howarth , Joel Giedt

The persistence diagram, which describes the topological features of a dataset, is a key descriptor in Topological Data Analysis. The "Discrete Morse Sandwich" (DMS) method has been reported to be the most efficient algorithm for computing…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-10-27 Eve Le Guillou , Pierre Fortin , Julien Tierny

Design of modern nanostructured semiconductor devices often calls for simulation tools capable of modeling arbitrarily-shaped multiscale geometries. In this work, to this end, a discontinuous Galerkin (DG) method-based framework is…

Computational Physics · Physics 2020-02-03 Liang Chen , Hakan Bagci

GS2 is an initial value gyrokinetic simulation code developed to study low-frequency turbulence in magnetized plasma. It is parallelised using MPI with the simulation domain decomposed across tasks. The optimal domain decomposition is…

Distributed, Parallel, and Cluster Computing · Computer Science 2014-10-30 Adrian Jackson , Joachim Hein , C. M. Roach

In this paper, we propose to use the discretized version of the so-called Enhanced Gaussian Noise (EGN) model to estimate the non-linearity effects of fiber on the performance of optical coherent and uncompensated transmission (CUT)…

Signal Processing · Electrical Eng. & Systems 2020-02-19 Ramin Hashemi , Mehdi Habibi , Hamzeh Beyranvand , Ali Emami , Mahdi Hashemi , Davood Ranjbar Rafie

The analysis of dissipatively coupled oscillators is challenging and highly relevant in power grids. Standard mathematical methods are not applicable, due to the lack of network symmetry induced by dissipative couplings. Here we demonstrate…

Adaptation and Self-Organizing Systems · Physics 2022-09-07 Robin Delabays , Saber Jafarpour , Francesco Bullo

We revisit the problem of non-parametric closed-loop identification in frequency domain; we give a brief survey of the literature and provide a small noise analysis of the direct, indirect, and joint input-output methods when two…

Systems and Control · Electrical Eng. & Systems 2024-11-13 Mohamed Abdalmoaty , Roy S. Smith

The knowledge of effective masses is a key ingredient to analyze numerous properties of semiconductors, like carrier mobilities, (magneto-)transport properties, or band extrema characteristics yielding carrier densities and density of…

We evaluate properties of neutral mesons in Nf=2 dynamical simulations of TMQCD at maximal twist. The pion is explored - establishing the size of the isospin splitting (an order a^2 effect). We investigate the eta' (the Nf=2 flavour singlet…

High Energy Physics - Lattice · Physics 2008-11-26 ETM Collaboration , Chris Michael , Carsten Urbach

Efficiently estimating large numbers of non-commuting observables is an important subroutine of many quantum science tasks. We present the derandomized shallow shadows (DSS) algorithm for efficiently learning a large set of non-commuting…

Feynman loop integrals are a key ingredient for the calculation of higher order radiation effects, and are responsible for reliable and accurate theoretical prediction. We improve the efficiency of numerical integration in sector…

High Energy Physics - Phenomenology · Physics 2016-01-12 Zhao Li , Jian Wang , Qi-Shu Yan , Xiaoran Zhao