English
Related papers

Related papers: Chiral three-nucleon force at N^4LO I: Longest-ran…

200 papers

We calculate neutrino processes involving two nucleons at subnuclear densities using chiral effective field theory. Shorter-range noncentral forces reduce the neutrino rates significantly compared with the one-pion exchange approximation…

Nuclear Theory · Physics 2009-11-06 S. Bacca , K. Hally , C. J. Pethick , A. Schwenk

The low-energy effective theory of nuclear physics based on chiral symmetry is reviewed. Topics discussed include the nucleon-nucleon force, few-body potentials, isospin violation, pion-deuteron scattering, proton-neutron radiative capture,…

High Energy Physics - Phenomenology · Physics 2009-10-30 U. van Kolck

The chiral two-pion exchange nucleon-nucleon interaction has nowadays a rather firm conceptual basis, but depends on low-energy constants, which may be extracted from fits to data. In order to facilitate this kind of application, we present…

Nuclear Theory · Physics 2007-05-23 R. Higa , M. R. Robilotta , C. A. da Rocha

We use Bayesian methods and Hamiltonian Monte Carlo (HMC) sampling to infer the posterior probability density function (PDF) for the low-energy constants (LECs) up to next-to-next-to-next- to-leading order (N3LO) in a chiral effective field…

Nuclear Theory · Physics 2024-07-29 Isak Svensson , Andreas Ekström , Christian Forssén

We evaluate the amplitude for $\gamma \gamma \rightarrow \pi^0 \pi^0$ to two loops in chiral perturbation theory. The three new counterterms which enter at this order in the low-energy expansion are estimated with resonance saturation. We…

High Energy Physics - Phenomenology · Physics 2011-07-19 S. Bellucci , J. Gasser , M. E. Sainio

Previous extrapolations of lattice QCD results for the nucleon mass to the physically relevant region of small quark masses, using chiral effective field theory, are extended and expanded in several directions. A detailed error analysis is…

High Energy Physics - Lattice · Physics 2007-05-23 M. Procura , B. U. Musch , T. Wollenweber , T. R. Hemmert , W. Weise

We discuss renormalization of chiral nuclear forces in the 3P0 channel of N N scattering at next- to-next-to leading order (N2LO) if the one-pion exchange is treated nonperturbatively at leading order. The matrix elements of the subleading…

Nuclear Theory · Physics 2024-11-22 Rui Peng , Bingwei Long , Fu-Rong Xu

We study pion--nucleon scattering with a chiral lagrangian of pions, nucleons, and $\Delta$-isobars. The scattering amplitude is evaluated to one-loop $Q^3$ order, where $Q$ is a generic small momentum, using a new approach which is…

High Energy Physics - Phenomenology · Physics 2008-11-26 Paul J. Ellis , Hua-Bin Tang

We present technical details of the evaluation of the elastic pi-pi scattering amplitude to two loops in chiral perturbation theory. In particular, we elaborate on the renormalization procedure at the two-loop order and on the evaluation of…

High Energy Physics - Phenomenology · Physics 2009-10-30 J. Bijnens , G. Colangelo , G. Ecker , J. Gasser , M. E. Sainio

We present predictions for the neutron matter equation of state, from leading to fourth order of chiral effective field theory, using recently developed, accurate chiral nucleon-nucleon potentials. We find the impact of subleading…

Nuclear Theory · Physics 2021-09-15 Francesca Sammarruca , Randy Millerson

These lectures give an introduction to baryon chiral perturbation theory. I show in detail how to construct the chiral effective pion-nucleon Lagrangian in the one loop approximation. Particular emphasis is put on the physics related to…

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

We sample the posterior probability distributions of the low-energy constants (LECs) in $\Delta$-full chiral effective field theory ($\chi$EFT) up to third order. We use eigenvector continuation for fast and accurate emulation of the…

Nuclear Theory · Physics 2024-07-29 Isak Svensson , Andreas Ekström , Christian Forssén

We present a dispersive method which allows to investigate the low-energy couplings of chiral perturbation theory at the next-to-leading order (NLO) in the 1/N(C) expansion, keeping full control of their renormalization scale dependence.…

High Energy Physics - Phenomenology · Physics 2010-10-27 I. Rosell , J. J. Sanz-Cillero , A. Pich

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…

We study the three-nucleon force in chiral effective field theory with explicit Delta-resonance degrees of freedom. We show that up to next-to-next-to-leading order, the only contribution to the isospin symmetric three-nucleon force…

Nuclear Theory · Physics 2008-11-26 E. Epelbaum , H. Krebs , Ulf-G. Meißner

An exploratory study of chiral four-nucleon interactions in nuclear and neutron matter is performed. The leading-order terms arising from pion-exchange in combination with the chiral $4\pi$-vertex and the chiral NN$3\pi$-vertex are found to…

Nuclear Theory · Physics 2015-06-11 N. Kaiser

We consider the relationship between P-wave pi-N scattering and the strength of the P-wave two-pion-exchange three-nucleon interaction (TPE3NI). We explain why effective theories that do not contain the delta resonance as an explicit degree…

Nuclear Theory · Physics 2009-04-17 V. R. Pandharipande , D. R. Phillips , U. van Kolck

A representation of the two-loop contribution to the pion decay constant in $SU(3)$ chiral perturbation theory is presented. The result is analytic upto the contribution of the three (different) mass sunset integrals, for which an expansion…

High Energy Physics - Phenomenology · Physics 2017-10-06 B. Ananthanarayan , Johan Bijnens , Shayan Ghosh

I review recent results in baryon chiral perturbation theory, in particular related to pion-nucleon scattering and first systematic attempts to go beyond next-to-leading order in the case of three flavors. New insight into the chiral…

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

We analyze the octet baryon masses and the pion/kaon--nucleon $\sigma$--terms in the framework of heavy baryon chiral perturbation theory. We include {\it all} terms up-to-and-including quadratic order in the light quark masses, $m_q$. We…

High Energy Physics - Phenomenology · Physics 2009-10-28 B. Borasoy , Ulf-G. Meißner