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Related papers: Excited states in nucleon structure calculations

200 papers

Multi-particle states with additional pions are expected to be a non-negligible source of the excited-state contamination in lattice simulations at the physical point. It is shown that baryon chiral perturbation theory (ChPT) can be…

High Energy Physics - Lattice · Physics 2018-04-18 Oliver Bar

We study the mass spectra of excited baryons with the use of the lattice QCD simulations. We focus our attention on the problem of the level ordering between the positive-parity excited state N'(1440) (the Roper resonance) and the…

High Energy Physics - Lattice · Physics 2009-11-11 Kiyoshi Sasaki , Shoichi Sasaki , Tetsuo Hatsuda

We summarize recent evidence, both from lattice QCD and chiral perturbation theory, that suggests that larger-than-expected excited-state contamination could be the reason for the tension between phenomenological determinations and previous…

High Energy Physics - Lattice · Physics 2022-03-29 Rajan Gupta , Tanmoy Bhattacharya , Martin Hoferichter , Emanuele Mereghetti , Sungwoo Park , Boram Yoon

Positive-parity spin-1/2 excitations of the nucleon are explored in lattice QCD. The variational method is used in this investigation and several correlation matrices are employed. As our focus is on the utility and methodology of the…

High Energy Physics - Lattice · Physics 2010-12-28 M. S. Mahbub , Alan Ó Cais , Waseem Kamleh , Derek B. Leinweber , Anthony G. Williams

In this work, we apply black box methods (methods not requiring input) to find excited-state energies. A variety of such methods for lattice QCD were introduced at the 3rd iteration of the numerical workshop series. We first review a…

High Energy Physics - Lattice · Physics 2007-09-13 Huey-Wen Lin , Saul D. Cohen

Progress in extracting excited-state baryon masses in lattice QCD using large sets of spatially-extended operators is presented. The use of stochastic estimates of all-to-all quark propagators with variance reduction techniques is…

High Energy Physics - Lattice · Physics 2019-08-13 Colin Morningstar

The current status of calculations of simple nucleon structure observables is reviewed, with a focus on the axial charge. A major challenge is the combination of an exponentially decaying signal-to-noise ratio and the need for large…

High Energy Physics - Lattice · Physics 2018-12-31 Jeremy Green

Progress in extracting the spectrum of excited hadron resonances is reviewed and the key issues and challenges in such computations are outlined. The importance of multi-hadron states as simulations are done with lighter pion masses is…

High Energy Physics - Lattice · Physics 2010-04-23 Colin Morningstar

A determination of the excited energy eigenstates of the nucleon, $s=c{1}{2}$, $I={1}{2}$, $N^{\pm}$, is presented in full QCD using 2+1 flavor PACS-CS gauge configurations. The correlation-matrix method is used and is built using standard…

High Energy Physics - Lattice · Physics 2013-06-26 M. Selim Mahbub , Waseem Kamleh , Derek B. Leinweber , Peter J. Moran , Anthony G. Williams

Energies for excited isospin 1/2 states that include the nucleon are computed using quenched, anisotropic lattices. Baryon interpolating field operators that are used include nonlocal operators that provide $G_2$ irreducible representations…

High Energy Physics - Lattice · Physics 2007-05-23 S. Basak , R. G. Edwards , G. T. Fleming , A. Lichtl , C. Morningstar , D. G. Ricards , I. Sato , S. J. Wallace

We review recent results on hadron form factors and nucleon generalized parton distibutions obtained with dynamical lattice QCD simulations. We discuss lattice artifacts and open questions, and present the connection of lattice results to…

High Energy Physics - Lattice · Physics 2010-12-10 C. Alexandrou

I review recent results on phase structure and equation of state of strong interaction matter from lattice QCD. Particular emphasis is given to the axes where direct simulations are possible and results are obtained with sufficient control…

High Energy Physics - Lattice · Physics 2025-12-12 Bastian B. Brandt

We present updated preliminary results for the nucleon electromagnetic form factors for non-perturbatively $\mathcal{O}(a)$ improved Wilson fermions in $N_f=2$ QCD measured on the CLS ensembles. The use of the summed operator insertion…

Recent results on the equation of state from lattice QCD are reviewed. The lattice technique and previous results are shortly discussed. New results for physical quark masses and two sets of lattice spacings are presented. The pressure,…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. D. Katz

The equation of state of QCD at finite temperatures and baryon densities has a wide range of applications in many fields of modern particle and nuclear physics. It is the main ingredient to describe the dynamics of experimental heavy ion…

High Energy Physics - Lattice · Physics 2015-06-05 Owe Philipsen

Two important sources of systematic errors in lattice QCD calculations of radiative leptonic decays are unwanted exponentials in the sum over intermediate states and unwanted excited states created by the meson interpolating field.…

High Energy Physics - Lattice · Physics 2021-12-02 Christopher Kane , Davide Giusti , Christoph Lehner , Stefan Meinel , Amarjit Soni

The contribution of the strange-quark current to the electromagnetic form factors of the nucleon is studied using lattice QCD. The strange current matrix elements from our lattice calculation are analyzed in two different ways, the…

High Energy Physics - Phenomenology · Physics 2017-08-23 R. Lewis , W. Wilcox , R. M. Woloshyn

We construct a family of equations of state within a quasiparticle model by relating pressure, energy density, baryon density and susceptibilities adjusted to first-principles lattice QCD calculations. The relation between pressure and…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Bluhm , B. Kampfer , R. Schulze , D. Seipt , U. Heinz

A few chosen nucleon properties are described from a lattice QCD perspective: the nucleon sigma term and the scalar strangeness in the nucleon; the vector form factors in the nucleon, including the vector strangeness contribution, as well…

High Energy Physics - Lattice · Physics 2015-05-28 Harvey B. Meyer

We present updated results for the nucleon axial charge and electromagnetic (EM) form factors, which include a significant increase in statistics for all ensembles (up to 4000 measurements), as well as the addition of ensembles with pion…

High Energy Physics - Lattice · Physics 2014-04-09 B. Jäger , T. D. Rae , S. Capitani , M. Della Morte , D. Djukanovic , G. von Hippel , B. Knippschild , H. B. Meyer , H. Wittig