Related papers: Isospin Violations in the Pion-Nucleon System
It is shown that isospin-breaking corrections to the pion-deuteron scattering length can be very large, because of the vanishing of the isospin-symmetric contribution to this scattering length at leading order in chiral perturbation theory.…
Recent studies have completed the A=16 isospin quintets for states with spin/parity J{\pi} =0+ and 2+. The dependence of their masses as a function of isospin projection shows evidence for deviations from quadratic behavior indicating…
The Heisenberg uncertainty inequality is used to derive a rigorous lower bound to the amount of isospin impurities in $N=Z$ atomic nuclei, caused by the violation of isospin symmetry. The bound is fixed by the difference between the neutron…
To understand the isospin effects in nearly symmetric nuclear matter we performed a complete systematical theoretical study within an Isospin dependent Quantum Molecular Dynamical Model (IQMD) and using Minimum Spanning Tree (MST)…
We provide a systematic study of the isospin composition and neutron-to-proton $\left( \frac{N}{Z} \right)$ ratio dependence of nuclear short-range correlations (SRC) across the nuclear mass table. We use the low-order correlation operator…
The in-medium neutron-proton, proton-proton(neutron-neutron) scattering cross sections($\sigma_{np}^{*}$, $\sigma_{pp(nn)}^{*}$) are studied based on QHD-II type Lagrangian within the framework of the microscopic transport theory. The…
A measurement of parity-violating spin-dependent gamma proton Compton scattering will provide a theoretically clean determination of the parity-violating pion-nucleon coupling constant $h_{\pi NN}^{(1)}$. We calculate the leading…
We present results on the pseudoscalar meson masses from a fully dynamical simulation of QCD+QED. We concentrate particularly on violations of isospin symmetry. We calculate the $\pi^+$-$\pi^0$ splitting and also look at other isospin…
An isospin analysis of $B\to\pi\pi$ decays yields $\sin 2\alpha$, where $\alpha$ is the usual CKM angle $\alpha\equiv arg [-V_{td}V_{tb}^\ast /(V_{ud}V_{ub}^\ast)]$, without hadronic uncertainty if isospin is a perfect symmetry. Isospin,…
We investigate the isospin dependence of pseudospin symmetry in the chain of tin isotopes (from $^{120}$Sn until $^{170}$Sn). Using a Woods-Saxon parametrization of the nuclear potential for these isotopes we study in detail the effect of…
Within the framework of the quantum molecular dynamics transport model, the pion production and constraint of the high-density symmetry energy in heavy-ion collisions near threshold energy have been thoroughly investigated. The energy…
The statistical system of pions with zero total isospin is studied. The suppression effects for the average yields due to isospin conservation are the same for $\pi^0$, $\pi^+$ and $\pi^-$. However, a behavior of the corresponding particle…
In nuclear collisions induced by stable or radioactive neutron-rich nuclei a transient state of nuclear matter with an appreciable isospin asymmetry as well as thermal and compressional excitation can be created. This offers the possibility…
A meson exchange model of the $\pi\pi$ interaction which fits free $\pi\pi$ scattering data is used to calculate the interactions of pions in nuclear matter as a function of nuclear density. Polarization of the nuclear medium by the pions…
A microscopic model for the $N\bar N\to\pi\pi$ process is presented in the meson exchange framework, which in the pseudophysical region agrees with available quasiempirical information. The scalar ($\sigma$) and vector ($\rho$) piece of…
The violation of isospin symmetry in nucleus-nucleus reactions, as shown in the ratio ${R_K=(K^++K^-)/(K^0+\bar{K}^0)}$ presented by NA61/SHINE, can be understood by introducing results from color-string fragmentation in $e^+e^-$ to nuclear…
Unlike their lighter counterparts, most odd-odd N=Z nuclei with mass A > 40 40 have ground states with isospin T=1, suggesting an increased role for the isovector pairing interaction. A simple SO(5) seniority-like model of this interaction…
Isospin is an approximate symmetry in atomic nuclei, arising from the rather similar properties of protons and neutrons. Perhaps the clearest manifestation of isospin within nuclei is in the near-identical structure of excited states in…
We pursue the calculation of the model-independent component of the axion-photon-photon coupling in the $U(3)$ chiral perturbation theory up to next-to-leading order, with the emphasis on the isospin breaking effect. The mixing of the…
I discuss the whole mechanism to calculate isospin violation effects in the framework of CHPT. In order to get the correct size of isospin violation one has to include all non-isospin symmetric sources like the electromagnetic interaction,…