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Related papers: Chiral baryon in the coherent pair approximation

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We investigate the parity-violating analyzing power in neutron capture on the proton at thermal energies in the framework of chiral effective field theory. By combining this analysis with a previous analysis of parity violation in…

Nuclear Theory · Physics 2015-06-15 J. de Vries , N. Li , Ulf-G. Meißner , A. Nogga , E. Epelbaum , N. Kaiser

I discuss low-energy pion-nucleon scattering in the framework of chiral perturbation theory. I argue that using this theoretical method one is able to handle the in some cases tremendous experimental accuracy (for the low partial waves). I…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ulf-G. Meißner

We extend the standard second order effective chiral Lagrangian of pions and nucleons by considering the coupling to an external gravitational field. As an application we calculate one-loop corrections to the one-nucleon matrix element of…

High Energy Physics - Phenomenology · Physics 2020-11-04 H. Alharazin , D. Djukanovic , J. Gegelia , M. V. Polyakov

Partial restoration in nuclear matter of the chiral symmetry of QCD is discussed together with some of its possible signals. Estimates of corrections to the leading, linear dependence of the quark condensate are found to be small, implying…

Nuclear Theory · Physics 2009-10-28 Michael C. Birse

Chiral perturbation theory is the effective field theory of the strong interactions at low energies. We will give a short introduction to chiral perturbation theory for mesons and will discuss, as an example, the electromagnetic…

High Energy Physics - Phenomenology · Physics 2015-06-25 Stefan Scherer

We have previously calculated the pion-nucleon $\Sigma_{\pi N}$ term in the chiral mixing approach with $u,d$ flavors only, and found the lower bound $\Sigma_{\pi N} \geq \left(1 + \frac{16}{3} \sin^2 \theta \right){3 \over 2}…

High Energy Physics - Phenomenology · Physics 2018-12-11 V. Dmitrasinovic , Hua-Xing Chen , Atsushi Hosaka

We base our chiral symmetry approach on the quark-level linear sigma model Lagrangian. Then we review the Nambu--Goldstone theorem with vanishing pi, K, eta_8 masses. Next we dynamically generate the pi, K, eta_8 masses away from the chiral…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Kekez , D. Klabucar , M. D. Scadron

We study the nuclear matter solution in the chiral quark soliton model coupled to $\rho$ and $\omega$ vector mesons based on the Wigner-Seitz approximation. It is shown that the vector mesons stabilize the soliton at high-density region. As…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Nagai , N. Sawado , N. Shiiki

The pheomenological Generalized Coherent State Model Hamiltonian is amended with a many body term describing a set of nucleons moving in a shell model mean-field and interacting among themselves with paring, as well as with a particle-core…

Nuclear Theory · Physics 2016-03-08 A. A. Raduta , Al. H. Raduta , C. M. Petrache

We study the nucleon and three N* resonances' properties in an effective linear realization chiral SU_L(2) x SU_R(2) and U_A(1) symmetric Lagrangian. We place the nucleon fields into the so-called "naive" (1/2,0) + (0, 1/2) and "mirror" (0,…

High Energy Physics - Phenomenology · Physics 2010-03-24 V. Dmitrasinovic , A. Hosaka , K. Nagata

We study the latest $N_f=2+1+1$ and $N_f=2$ ETMC lattice QCD simulations of the nucleon masses and extract the pion-nucleon sigma term utilizing the Feynman-Hellmann theorem in SU(2) baryon chiral perturbation theory with the…

High Energy Physics - Phenomenology · Physics 2018-07-13 Xiu-Lei Ren , Xi-Zhe Ling , Li-Sheng Geng

We report on recent progress on the chiral unitary approach, which is shown to have a much larger convergence radius than ordinary chiral perturbation theory, allowing one to reproduce data for meson meson interaction up to 1.2 GeV and…

High Energy Physics - Phenomenology · Physics 2009-10-31 E. Oset , A. Hosaka , J. C. Nacher , M. Oka , J. A. Oller , A. Parreno , J. R. Pelaez , A. Ramos , H. Toki

We study radiative corrections to low-energy charged-current processes involving nucleons, such as neutron beta decay and (anti)neutrino-nucleon scattering within a top-down effective-field-theory approach. We first match the Standard Model…

High Energy Physics - Phenomenology · Physics 2023-09-08 Vincenzo Cirigliano , Wouter Dekens , Emanuele Mereghetti , Oleksandr Tomalak

We analyze recent measurements of the nucleon quark sea isospin asymmetry in terms of the chiral quark model. The new measurements indicate that the SU(3) model with modest symmetry breaking and no $\eta'$ Goldstone boson gives a…

High Energy Physics - Phenomenology · Physics 2011-09-13 Tommy Ohlsson , Hakan Snellman

The chiral nonlinear ($\sigma,\pi,\omega$) mean-field model is an extension of the conserving nonlinear (nonchiral) $\sigma$-$\omega$ hadronic mean-field model which is thermodynamically consistent, relativistic and Lorentz-covariant…

Nuclear Theory · Physics 2010-11-24 Schun T. Uechi , Hiroshi Uechi

We present an accurate nucleon-nucleon ($NN$) potential based upon chiral effective Lagrangians. The model includes one- and two-pion exchange contributions up to chiral order three. We show that a quantitative fit of the $NN$ $D$-wave…

Nuclear Theory · Physics 2010-04-06 D. R. Entem , R. Machleidt

We calculate the nuclear structure corrections to the Lamb shift in muonic deuterium by using state-of-the-art nucleon-nucleon potentials derived from chiral effective field theory. Our calculations complement previous theoretical work…

Nuclear Theory · Physics 2014-08-19 Oscar Javier Hernandez , Chen Ji , Sonia Bacca , Nir Nevo Dinur , Nir Barnea

We describe a model for pion production off nucleons and coherent pions from nuclei induced by neutrinos in the 1 GeV energy regime. Besides the dominant Delta pole contribution, it takes into account the effect of background terms required…

Nuclear Theory · Physics 2017-08-23 M. Valverde , J. E. Amaro , E. Hernandez , J. Nieves , M. J. Vicente Vacas

We show how the unitarized description of pion nucleon scattering within Heavy Baryon Chiral Perturbation Theory can be considerably improved, by a suitable reordering of the expansion over the nucleon mass. Within this framework, the…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. Gómez Nicola , J. Nieves , J. R. Peláez , E. Ruiz Arriola

We derive the expressions of the vector and axial current from a chiral Lagrangian restricted to nucleons and pions. They display mixing terms between the axial and vector currents. We study the modifications in the nuclear medium of the…

Nuclear Theory · Physics 2009-10-31 G. Chanfray , J. Delorme , M. Ericson