Related papers: A microscopic NN to NN*(1440) potential
The chiral symmetry is applied to an extended constituent quark potential model. With random phase approximation (RPA), the model comprises sea quark excitations. To obtain the pseudoscalar $\pi$ meson as a Goldstone boson, the quark…
Single-neutron transfer reactions populating states in the continuum are interesting both for structure and astrophysics. In their description often global optical potentials are used for the nucleon-target interactions, and these…
The weak $\Lambda N\to NN$ transition is studied in the valence quark model approach. The quark component of the two baryon system is described in the quark cluster model and the weak transition potential is calculated by evaluating the…
Radiative capture reactions for low energy protons have been theoretically studied for Ni and Cu isotopes using the microscopic optical model. The optical potential has been obtained in the folding model using different microscopic…
A constituent quark model is developed for the reaction, allowing us to investigate all available data for differential cross sections as well as single polarization asymmetries (beam and target) by including {\it all} of the PDG, one to…
We calculate in baryon chiral perturbation theory the relativistic $1/M^2$-corrections to the leading order two-pion exchange diagrams. We give explicit expressions for the corresponding one-loop NN-amplitudes in momentum space. The…
In this paper we compare a model that contains the mechanisms of $\Delta$ excitation in the projectile and Roper excitation in the target with experimental data from two (d, d') experiments on a proton target. The agreement of the theory…
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…
A self-consistent relativistic integral-differential equation of the Boltzmann-Uehling-Uhlenbeck-type for the $N^{*}$(1440) resonance is developed based on an effective Lagrangian of baryons interacting through mesons. The closed time-path…
The pion-mass-dependent nucleon-nucleon ($NN$) potentials in term of one-pion exchange and contact terms are obtained from the latest lattice QCD simulations of two-nucleon system, which employ the forms of leading order (LO) $NN$ potential…
Results are presented for a combined analysis of the reactions $pp\to pp$, $\pi d\to \pi d$ and $\pi d\to pp$ over the $\sqrt{s}$ interval from pion threshold to approximately 2.4 GeV. These results for $\pi d\to pp$ and $\pi d$ elastic…
The reaction pi N -> pi pi N is studied at tree level up to next-to-leading order in the framework of manifestly covariant baryon chiral perturbation theory with explicit Delta(1232) degrees of freedom. Using total cross section data to…
The Roper resonance is described in a chiral version of the chromodielectric model as a cluster of three quarks in radial-orbital configuration (1s)$^2$(2s)$^1$, surrounded by $\pi$ and $\sigma$-meson clouds and by a chromodielectric field…
Recent results for the QCD phase structure at finite temperature and light-quark chemical potential are summarized, where the cases of N_f = 2 + 1 and N_f = 2+1+1 dynamical quark flavors are considered. Order parameters for the chiral and…
A fermion model with random on-site potential defined on a two-dimensional square lattice with $\pi$-flux is studied. The continuum limit of the model near the zero energy yields Dirac fermions with random potentials specified by four…
The neutron capture cross section for $^{90}Zr(n, \gamma)$ has recently been determined using surrogate $^{92}Zr(p, d\gamma)$ data and nuclear reaction theory. That work employed an approximate fitting method based on Bayesian Monte Carlo…
We calculate in heavy baryon chiral perturbation theory the local NN-potentials generated by the two-pion exchange diagrams at two-loop order. We give explicit expressions for the mass-spectra (or imaginary parts) of the corresponding…
Cross section of the neutron capture reaction $n+p\rightarrow d+\gamma$ at threshold was calculated with different realistic $^{3}S_{1}$ deuteron and $^{1}S_{0}$ $np$ scattering wave functions stemming from Nijmegen-II, JISP16, Paris, Idaho…
Differential cross sections of the reactions $pp \to d\pi^+$ and $pp \to pn\pi^+$ have been measured at $T_p = 400$ MeV by detecting the charged ejectiles in the angular range $4^0 \leq \Theta_{Lab} \leq 21^\circ$. The deduced total cross…
We present a simple model for the $\gamma N \to \pi \pi N$ reaction which reproduces the cross sections of the $\pi^+ \pi^- p, \pi^+ \pi^- n, \pi^+ \pi^0 n$ and $\pi^- \pi^0 p$ channels over the range of the energies 0.41-0.85 GeV. We use…