Related papers: Isospin violation in the two-nucleon system
Recent phenomenological work has examined two different ways of including charge symmetry violation in parton distribution functions. First, a global phenomenological fit to high energy data has included charge symmetry breaking terms,…
We study nucleon-nucleon scattering on the lattice at next-to-leading order in chiral effective field theory. We determine phase shifts and mixing angles from the properties of two-nucleon standing waves induced by a hard spherical wall in…
In recent years, high-accuracy data for pionic hydrogen and deuterium have become the primary source of information on the pion-nucleon scattering lengths. Matching the experimental precision requires, in particular, the study of…
Isospin symmetry of atomic nuclei is explicitly broken by the charge-dependent interactions, primarily the Coulomb force. Within the nuclear density functional theory, isospin is also broken spontaneously. We propose a projection scheme…
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…
We derive the leading contribution to the four-nucleon force within the framework of chiral effective field theory. It is governed by the exchange of pions and the lowest-order nucleon-nucleon contact interaction and includes effects due to…
We review to what extent charge independence breaking (\emph{CIB}) in isospin related reactions of the type $NN\to d\pi$ can or could be seen in existing data. In doing this we present fits to global and threshold cross sections including…
Recently, a global phenomenological fit to high energy data has included charge symmetry breaking terms, leading to limits on the allowed magnitude of such effects. We discuss two possible experiments that could search for isospin violation…
The observed isospin-symmetry breaking in light nuclei are caused not only by the Coulomb interaction but by the isovector one and two body plus isotensor two body nuclear interactions as well. Spectral distribution theory which treats…
We calculate in chiral perturbation theory the parity-violating two-pion exchange nucleon-nucleon potentials at leading one-loop order. At a distance of $r= m_\pi^{-1} \simeq 1.4 $fm they amount to about $\pm 16%$ of the parity-violating…
We consider the two-nucleon system at next-to-next-to-next-to-leading order (N^3LO) in chiral effective field theory. The two-nucleon potential at N^3LO consists of one-, two- and three-pion exchanges and a set of contact interactions with…
In the rest frame of a many-body system, used in the calculation of its static and scattering properties, the center of mass of a two-body subsystem is allowed to drift. We show, in a model independent way, that drift corrections to the…
Extraction of the nucleon's strange form factors from experimental data requires a quantitative understanding of the unavoidable contamination from isospin violation. A number of authors have addressed this issue during the past decade, and…
We evaluate the isospin breaking corrections to the scattering amplitude \pi^- K^+ -> \pi^- K^+ at threshold in the framework of chiral perturbation theory. This channel is of particular interest for the strong 2S-2P energy level shift in…
Nonperturbative effective field theory calculations for NN scattering seem to break down at rather low momenta. By examining several toy models, we clarify how effective field theory expansions can in general be used to properly separate…
We study relationship between the physical quantities that characterize pion-nucleon and nucleon-nucleon interaction on the basis of the fact that nuclear forces in the nucleon-nucleon system at low energies are mainly determined by the…
Nuclear processes involving momenta much below the mass of the pion may be described by an effective field theory in which the pions do not appear as explicit degrees of freedom. The effects of the pion and all other virtual hadrons are…
High energy reactions may produce a state around the collision point that is best described by a classical pion field. Such a field might be an isospin rotated vacuum of the chiral $\sigma$-model or, as discussed in this work, a solution of…
The charge-symmetry-breaking amplitudes for the recently observed d d -> alpha pi0 reaction are investigated. Chiral perturbation theory is used to classify and identify the leading-order terms. Specific forms of the related one- and…
To understand the role of isospin effects on fragmentation due to the collisions of charge asymmetric nuclei, we have performed a complete systematical study using isospin dependent quantum molecular dynamics model. Here simulations have…