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Related papers: Delta-excitations and the three-nucleon force

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The isospin breaking in the nucleon isovector axial charge, $g_A^3$, are calculated within the external field QCD sum-rule approach. The isospin violations arising from the difference in up and down current quark masses and in up and down…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xuemin Jin

The charge-exchange break-up of polarised deuterons pol{d}p -> {pp}n, where the final {pp} diproton system has a very low excitation energy and hence is mainly in the 1S0 state, is a powerful tool to probe the spin-flip terms in the…

Long-range contributions to the three-nucleon force that have been recently worked out in chiral effective field theory at next-to-next-to-next-to-leading order are for the first time included in the triton and the doublet nucleon-deuteron…

Nuclear Theory · Physics 2013-05-29 R. Skibinski , J. Golak , K. Topolnicki , H. Witala , E. Epelbaum , W. Gloeckle , H. Krebs , A. Nogga , H. Kamada

We consider a new three-nucleon force generated by the exchange of one pion in the presence of a 2N correlation. The underlying irreducible diagram has been recently suggested by the authors as a possible candidate to explain the puzzle of…

Nuclear Theory · Physics 2009-11-06 L. Canton , W. Schadow

Faddeev equations for elastic Nd scattering have been solved using modern NN forces combined with the Tucson-Melbourne two-pion exchange three-nucleon force, with a modification thereof closer to chiral symmetry and the Urbana IX…

Nuclear Theory · Physics 2009-11-06 H. Witala , W. Gloeckle , J. Golak , A. Nogga , H. Kamada , R. Skibiński , J. Kuros-Zolnierczuk , .

We compute various nucleon polarizabilities in chiral perturbation theory implementing the $\Delta$-full ($\Delta$-less) approach up to order $\epsilon^3 + q^4$ ($q^4$) in the small-scale (chiral) expansion. The calculation is carried out…

Nuclear Theory · Physics 2021-03-10 M. Thürmann , E. Epelbaum , A. M. Gasparyan , H. Krebs

We study the importance of few-nucleon forces in chiral effective field theory for describing many-nucleon systems. A combinatorial argument suggests that three-nucleon forces -- which are conventionally regarded as next-to-next-to-leading…

Nuclear Theory · Physics 2023-10-06 C. -J. Yang , A. Ekström , C. Forssén , G. Hagen , G. Rupak , U. van Kolck

Using the two-loop approximation of chiral perturbation theory, we calculate the momentum and density dependent isovector nuclear spin-orbit strength $V_{ls}(p,k_f)$. This quantity is derived from the spin-dependent part of the interaction…

Nuclear Theory · Physics 2009-11-10 N. Kaiser

We explore the constraints on the three-nucleon force (3NF) of chiral effective field theory ($\chi$EFT) that are provided by bound-state observables in the $A=3$ and $A=4$ sectors. Our statistically rigorous analysis incorporates…

Results of an exploratory study of the antinucleon-nucleon interaction within chiral effective field theory are reported. The antinucleon-nucleon potential is derived up to next-to-next-to-leading order, based on a modified Weinberg power…

High Energy Physics - Phenomenology · Physics 2015-06-17 Xian-Wei Kang , Johann Haidenbauer , Ulf-G. Meißner

During the past two decades, chiral effective field theory has become a popular tool to derive nuclear forces from first principles. Two-nucleon interactions have been worked out up to sixth order of chiral perturbation theory and…

Nuclear Theory · Physics 2016-08-31 R. Machleidt , F. Sammarruca

We report on the first calculation of excited baryons with a chirally symmetric Hamiltonian, modeled after Coulomb gauge QCD (or upgraded from the Cornell meson potential model to a field theory in all of Fock-space) showing the…

High Energy Physics - Phenomenology · Physics 2008-10-28 Felipe J. Llanes-Estrada , Pedro Bicudo , Marco Cardoso , Tim Van Cauteren

Chiral Effective Field Theory is for photon energies up to 200 MeV the tool to accurately determine the polarisabilities of the neutron from deuteron Compton scattering. A multipole analysis reveals that dispersive effects from an explicit…

Nuclear Theory · Physics 2008-11-26 Harald W. Griesshammer

We calculate the electromagnetic, axial and pseudo-scalar form factors of the Nucleon to $\Delta(1232)$ transition using two dynamical light degenerate quarks and a dynamical strange quark simulated with the domain wall fermion action.…

High Energy Physics - Lattice · Physics 2011-02-25 C. Alexandrou , G. Koutsou , J. W. Negele , Y. Proestos , A. Tsapalis

We study the effects of the $\Delta$(1232) resonance as an effective degree of freedom for charged and neutral pion photo-production on nucleons. Different observables have been calculated for these processes by using relativistic chiral…

High Energy Physics - Phenomenology · Physics 2019-11-27 Gustavo H. Guerrero Navarro

We present a nucleon-nucleon potential at fifth order in chiral effective field theory. We find a substantial improvement in the description of nucleon-nucleon phase shifts as compared to the fourth-order results of Ref. [E. Epelbaum, H.…

Nuclear Theory · Physics 2015-09-23 E. Epelbaum , H. Krebs , U. -G. Meißner

The model for charge symmetry breaking in the reaction np --> dpi^0 applied earlier around the Delta region is used to calculate the integrated forward-backward asymmetry of the cross section close to threshold. The mixing of the pi and eta…

Nuclear Theory · Physics 2009-10-31 J. A. Niskanen

We consider multi-particle contributions to nucleon two- and three-point functions from the perspective of chiral dynamics. Lattice nucleon interpolating operators, which have definite chiral transformation properties, can be mapped into…

High Energy Physics - Lattice · Physics 2015-05-27 Brian C. Tiburzi

We investigate the parity-violating nucleon-nucleon potential as obtained in chiral effective field theory. By using resonance saturation we compare the chiral potential to the more traditional one-meson exchange potential. In particular,…

Nuclear Theory · Physics 2014-07-17 J. de Vries , N. Li , Ulf-G. Meißner , N. Kaiser , X. -H. Liu , S. -L. Zhu

I consider some selected topics in chiral perturbation theory (CHPT) as probed at colliders such as DA$\Phi$NE. Emphasis is put on processes involving pions in the isospin zero S-wave which require multi-loop calculations. These include the…

High Energy Physics - Phenomenology · Physics 2009-09-25 Ulf-G. Meißner