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Related papers: Nucleon sigma terms with a variational analysis fr…

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The RQCD collaboration proposed a projection method to remove the excited state contamination in lattice OCD calculations of nuclear form factors. The effectiveness of this method in removing the two-particle nucleon-pion-state…

High Energy Physics - Lattice · Physics 2020-02-28 Oliver Bar

We present preliminary results for the axial, scalar and tensor charges of the nucleon measured in 2+1 flavor QCD with the physical light quarks ($m_\pi=135$ MeV). Our simulations are carried out with gauge configurations generated by the…

High Energy Physics - Lattice · Physics 2023-01-18 Ryutaro Tsuji , Yasumichi Aoki , Ken-Ichi Ishikawa , Yoshinobu Kuramashi , Shoichi Sasaki , Eigo Shintani , Takeshi Yamazaki

We adopt the heavy baryon chiral perturbation theory to calculate the $\Sigma_cN$ interaction to the next-to-leading order. We consider the contact interactions, one-pion-exchange contributions, two-pion-exchange diagrams, and…

Nuclear Theory · Physics 2020-07-01 Lu Meng , Bo Wang , Shi-Lin Zhu

It is shown that the strong volume-dependence of the axial charge of the nucleon seen in lattice QCD calculations can be understood quantitatively in terms of the pion-induced interactions between neighbouring nucleons. The associated wave…

High Energy Physics - Lattice · Physics 2012-05-09 N. L. Hall , A. W. Thomas , R. D. Young , J. M. Zanotti

We use lattice QCD and the L\"uscher method to study elastic pion-nucleon scattering in the isospin $I = 3/2$ channel, which couples to the $\Delta(1232)$ resonance. Our $N_f=2+1$ flavor lattice setup features a pion mass of $m_\pi \approx…

We study the coupled pion-nucleon system (negative parity, isospin 1/2) based on a lattice QCD simulation for nf=2 mass degenerate light quarks. Both, standard 3-quarks baryon operators as well as meson-baryon (4+1)-quark operators are…

High Energy Physics - Lattice · Physics 2013-05-20 C. B. Lang , V. Verduci

We evaluate the nucleon sigma term and in-medium quark condensate in the modified quark-meson coupling model which features a density-dependent bag constant. We obtain a nucleon sigma term consistent with its empirical value, which requires…

Nuclear Theory · Physics 2009-10-30 Xuemin Jin , Manuel Malheiro

Recent results of meson photo-production at the existing electron machines with polarized real photon beams and the measurement of polarization observables of the final state baryons have provided high precision data that led to the…

Nuclear Experiment · Physics 2016-10-12 Volker D. Burkert

In this paper, we study the nucleon energy spectrum in the ground-state (with orbital momentum L=0) and the first excited state (L=1). The aim of this study is to find the mass and mixing angles of excited nucleons using a potential model…

High Energy Physics - Phenomenology · Physics 2007-05-23 I. K. Bensafa , F. Iddir , L. Semlala

We study the a0 and sigma mesons with the overlap fermion in the chiral regime with the pion mass as low as 182 MeV in the quenched approximation. After the eta'pi ghost states are separated, we find that the a0 mass with q\bar{q}…

High Energy Physics - Phenomenology · Physics 2008-11-26 Nilmani Mathur , A. Alexandru , Y. Chen , S. J. Dong , T. Draper , I. Horvath , F. X. Lee , K. F. Liu , S. Tamhankar , J. B. Zhang

We calculate the scalar and tensor charges of the nucleon in 2+1-flavor lattice QCD, for which the systematics of the renormalization of the disconnected diagram is well controlled. Numerical simulations are performed at a single lattice…

High Energy Physics - Lattice · Physics 2018-09-27 Nodoka Yamanaka , Shoji Hashimoto , Takashi Kaneko , Hiroshi Ohki

We performed a precise calculation of physical quantities related to the axial structure of the nucleon using 2+1 flavor lattice QCD gauge configuration (PACS10 configuration) generated at the physical point with lattice volume larger than…

In recent years, a persistent tension between phenomenological and lattice QCD determinations of the pion-nucleon $\sigma$-term $\sigma_{\pi N}$ has developed. In particular, lattice-QCD calculations have matured to the point that…

High Energy Physics - Phenomenology · Physics 2023-06-16 Martin Hoferichter , Jacobo Ruiz de Elvira , Bastian Kubis , Ulf-G. Meißner

We present results of our numerical calculation of the mass spectrum for isospin one-half and spin one-half non-strange baryons, i.e. the ground and excited states of the nucleon, in quenched lattice QCD. We use a new lattice discretization…

High Energy Physics - Lattice · Physics 2009-11-07 Shoichi Sasaki , Tom Blum , Shigemi Ohta

We study single-particle potential of Lambda, Sigma, and Xi hyperons in nucleonic matter starting from the fundamental theory of the strong interaction, QCD. First we carry out a lattice QCD numerical simulation, and extract baryon-baryon…

High Energy Physics - Lattice · Physics 2019-09-04 Takashi Inoue

We derive the equation of state of nuclear matter including vacuum polarization effects arising from the nucleons and the sigma mesons in the quark-meson coupling model which incorporates explicitly quark degrees of freedom with quark…

Nuclear Theory · Physics 2009-11-07 P. K. Panda , F. L. Braghin

We present results for the nucleon electromagnetic and axial form factors using an N$_f$=2 twisted mass fermion ensemble with pion mass of about 131 MeV. We use multiple sink-source separations to identify excited state contamination.…

We review the large-N_c approach to meson-baryon scattering, including recent interesting developments. We then study pion-nucleon scattering in a particular variant of the linear sigma-model, in which the couplings of the sigma and pi…

High Energy Physics - Phenomenology · Physics 2009-10-28 Michael P. MATTIS , Richard R. SILBAR

We present an updated analysis of meson-baryon sigma terms in the perturbative chiral quark model, which is based on effective chiral Lagrangian. The new feature concerns the inclusion of excited states in the quark propagator. Its…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Inoue , V. E. Lyubovitskij , Th. Gutsche , Amand Faessler

Baryon masses and nucleon \sigma-terms are studied with the effective theory that combines the chiral and 1/Nc expansions for three flavors. In particular the connection between the deviation of the Gell-Mann-Okubo relation and the…

High Energy Physics - Phenomenology · Physics 2018-05-23 I. P. Fernando , J. M. Alarcon , J. L. Goity