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相关论文: Three-particle $N\pi\pi$ state contribution to the…

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We investigate the reaction pn -> dpipi in the framework of Chiral Perturbation Theory. For the first time a complete calculation of the leading order contributions is presented. We identify various diagrams that are of equal importance as…

核理论 · 物理学 2015-05-19 Bochao Liu , Vadim Baru , Johann Haidenbauer , Christoph Hanhart

Lattice QCD is rapidly progressing toward being able to reliably compute the electric dipole moment of the neutron as a function of the strong CP-violating parameter theta. Present day calculations are performed at unphysical values of the…

高能物理 - 格点 · 物理学 2014-11-17 Donal O'Connell , Martin J. Savage

We determine the nucleon-sigma terms from lattice QCD. We find that the dominant excited state contamination in the nucleon three-point function with a scalar current is due to the transition between the nucleon and a S-wave scattering…

高能物理 - 格点 · 物理学 2025-01-30 Lorenzo Barca , Gunnar Bali , Sara Collins

The extrapolation of nucleon magnetic form factors calculated within lattice QCD is investigated within a framework based upon heavy baryon chiral effective-field theory. All one-loop graphs are considered at arbitrary momentum transfer and…

高能物理 - 唯象学 · 物理学 2008-11-26 P. Wang , D. B. Leinweber , A. W. Thomas , R. D. Young

We report the first Lattice QCD calculation using the almost physical pion mass mpi=149 MeV that agrees with experiment for four fundamental isovector observables characterizing the gross structure of the nucleon: the Dirac and Pauli radii,…

高能物理 - 格点 · 物理学 2014-08-04 J. R. Green , M. Engelhardt , S. Krieg , J. W. Negele , A. V. Pochinsky , S. N. Syritsyn

In the PACS10 project, the PACS collaboration has generated three sets of the PACS10 gauge configurations at the physical point with lattice volume larger than $(10\;{\rm fm})^4$ and three different lattice spacings. The isovector nucleon…

We propose a formalism to extract the $\gamma\pi\to\pi\pi$ chiral anomaly $F_{3\pi}$ from calculations in lattice QCD performed at larger-than-physical pion masses. To this end, we start from a dispersive representation of the…

高能物理 - 唯象学 · 物理学 2021-12-16 Malwin Niehus , Martin Hoferichter , Bastian Kubis

The leading chiral contributions to the quark and gluon components of the proton spin are calculated using heavy-baryon chiral perturbation theory. Similar calculations are done for the moments of the generalized parton distributions…

高能物理 - 唯象学 · 物理学 2009-11-07 Jiunn-Wei Chen , Xiangdong Ji

QCD matrix elements of axial and vector currents between nucleons are required for the Monte Carlo reconstruction of the energy of neutrinos that are detected in long baseline oscillation experiments in the quasi-elastic regime. The…

高能物理 - 格点 · 物理学 2023-03-28 Lorenzo Barca , Gunnar Bali , Sara Collins

Excited state contamination is one of the most challenging sources of systematics to tackle in the determination of nucleon matrix elements and form factors. The signal-to-noise problem prevents one from considering large source-sink time…

高能物理 - 格点 · 物理学 2021-10-25 Lorenzo Barca , Gunnar S. Bali , Sara Collins

An exploratory study is made of the nucleon-nucleon $s$-wave scattering lengths in quenched lattice QCD with the Wilson quark action. The $\pi$-$N$ and $\pi$-$\pi$ scattering lengths are also calculated for comparison. The calculations are…

高能物理 - 格点 · 物理学 2016-08-31 M. Fukugita , Y. Kuramashi , H. Mino , M. Okawa , A. Ukawa

We use QCD sum rules for the three point function of a pseudoscalar and two nucleonic currents in order to estimate the charge dependence of the pion nucleon coupling constant $g_{NN\pi}$ coming from isospin violation in the strong…

核理论 · 物理学 2008-11-26 T. Meissner , E. M. Henley

Neutrino oscillation experiments require accurate reconstructions of neutrino energies, which depend in part on a theoretical understanding of the axial $N \rightarrow \Delta$ transition form factors. Lattice QCD studies of this transition…

高能物理 - 格点 · 物理学 2023-12-25 Anthony V. Grebe , Michael Wagman

We present the dominant two- and three-pion-exchange contributions to the nucleon-nucleon interaction at sixth order (next-to-next-to-next-to-next-to-next-to-leading order, N5LO) of chiral perturbation theory. Phase shifts with orbital…

核理论 · 物理学 2015-12-16 D. R. Entem , N. Kaiser , R. Machleidt , Y. Nosyk

We present the two- and three-pion exchange contributions to the nucleon-nucleon interaction which occur at next-to-next-to-next-to-next-to-leading order (N4LO, fifth order) of chiral effective field theory, and calculate nucleon-nucleon…

核理论 · 物理学 2015-01-14 D. R. Entem , N. Kaiser , R. Machleidt , Y. Nosyk

We calculate the electric dipole moment of the nucleon induced by the QCD theta term. We use the gradient flow to define the topological charge and use $N_f = 2+1$ flavors of dynamical quarks corresponding to pion masses of $700$, $570$,…

高能物理 - 格点 · 物理学 2021-01-27 Jack Dragos , Thomas Luu , Andrea Shindler , Jordy de Vries , Ahmed Yousif

We calculate finite size effects on nucleon masses in chiral perturbation theory. We confront the theoretical predictions with N_f=2 lattice results and discuss chiral extrapolation formulae.

The $I=2$ $\pi\pi$ elastic $s$-wave scattering phase shift is measured by lattice QCD with $N_f=3$ flavors of the Asqtad-improved staggered fermions. The lattice-calculated energy-eigenvalues of $\pi\pi$ systems at one center of mass frame…

高能物理 - 格点 · 物理学 2024-09-23 Ziwen Fu , Jun Wang

We calculate the nucleon mass in a manifestly relativistic baryon chiral perturbation theory up to the leading two-loop order. Through dimensional counting analysis, we perform the chiral expansion and verify the validity of the…

高能物理 - 唯象学 · 物理学 2025-03-24 Ze-Rui Liang , Han-Xue Chen , Feng-Kun Guo , Zhi-Hui Guo , De-Liang Yao

Consideration of the analytic properties of pion-induced baryon self energies leads to new functional forms for the extrapolation of light baryon masses. These functional forms reproduce the leading non-analytic behavior of chiral…

核理论 · 物理学 2010-02-17 Anthony W. Thomas , Derek B. Leinweber , Kazuo Tsushima , Stewart V. Wright