相关论文: Radiative Neutron-Proton Capture in Effective Chir…
Exchange vector currents are calculated up to one-loop order (corresponding to next-to-next-to-leading order) in chiral perturbation theory. As an illustration of the power of the approach, we apply the formalism to the classic nuclear…
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…
Chiral perturbation theory in heavy-fermion formalism is developed for meson-exchange currents in nuclei and applied to nuclear axial- charge transitions. Calculation is performed to the next-to-leading order in chiral expansion which…
The radiative capture process n+p-> d+gamma provides clear evidence for meson exchange currents in nuclear physics. We compute this process at low energies using a recently developed power counting for the effective field theory that…
The meson-exchange current in nuclei, a long-standing problem in nuclear physics, is described in modern theory of strong interactions, namely, QCD expressed in terms of effective chiral Lagrangian field theory. Some old results are given a…
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 and contact terms (which represent the short range force) up…
The reaction $\gamma d\to \pi^+ nn$ is calculated up to order $\chi^{5/2}$ in chiral perturbation theory, where $\chi$ denotes the ratio of the pion to the nucleon mass. Special emphasis is put on the role of nucleon--recoil corrections…
Chiral symmetry serves as a guiding principle in low-energy hadron dynamics. An effective lagrangian, which explicitly breaks chiral symmetry via a small mass term, allows for a systematic method of calculating higher order corrections to…
After outlining the basic ideas of nuclear chiral perturbation theory, I discuss its application, presenting three examples which I believe are of great current interest: (1) Exchange currents in those cases where the leading chiral-order…
The cross section for radiative thermal neutron capture on ${}^{3}He$ ($\He3 +n \to \He4 +\gamma$; known as the $hen$ reaction) is calculated based on heavy-baryon chiral perturbation theory. The relevant M1 operators are derived up to…
This study presents a tree-level calculation of the scattering amplitude for the $lp\to lp\gamma$ (with a hard photon) process within the framework of Chiral Perturbation Theory. Our calculations, based on the $O(p^2)$ and $O(p^3)$…
We develop a systematic chiral perturbation expansion for the calculation of meson-exchange currents in nuclei and apply the formalism to nuclear axial currents. We summarize the principal results of such a calculation to one loop order on…
We calculate the energy-dependent cross section of the $np\leftrightarrow d\gamma$ process in chiral effective field theory and apply state-of-the-art tools for quantification of theory uncertainty. We focus on the low-energy regime, where…
We calculate in chiral perturbation theory the dominant next-to-leading order correction to the $\pi\gamma$-exchange NN-potential proportional to the large isovector magnetic moment $\kappa_v = 4.7$ of the nucleon. The corresponding…
We present a calculation of the radiative capture cross section $p(n,\gamma )d$ in the low-energy range, where the $M1$ reaction channel dominates. Employing the LENPIC nucleon-nucleon interaction up to the fifth order (N4LO) that is…
The transition operator for the radiative capture of mesons mu minus by protons is constructed starting from a chiral Lagrangian of the N-pi-rho-a_1-omega system obtained within the approach of hidden local symmetries. The transition…
We discuss the results of a systematic calculation of the next-to-next-to-leading order amplitude for the pp -> pp\pi^0 S-wave production at the threshold in heavy-baryon chiral perturbation theory. We find six new diagrams, two of which…
We construct a relativistic chiral nucleon-nucleon interaction up to the next-to-next-to-leading order in covariant baryon chiral perturbation theory. We show that a good description of the $np$ phase shifts up to $T_\mathrm{lab}=200$ MeV…
The nucleon-deuteron radiative capture process is investigated using the chiral nuclear potentials and the electromagnetic currents developed by the Bochum-Bonn group. While the strong interaction is taken up to the next-to-next-to-leading…
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…