Modeling of a microscopic optical pion-nucleon potential at energies in the (3, 3)-resonance region and nuclear-matter effect on the pion-nucleon amplitude

Comparative analysis of proton and pion scattering on the isotopes 6,8Не within Glauber theory

“…The sensitivity of the differential cross sections for proton and pion scattering to the input nuclear structure was tested in [8][9][10][42][43][44] via calculations with various wave functions and densities. It was shown that this sensitivity is the lowest at small scattering angles and that simpler models (for example, the shell and two-cluster models) may also reproduce data on forward scattering.…”

“…At the present time, emphasis is placed on an analysis on nuclear many-body problems (manifestation of tensor forces in pion charge-exchange processes [2,3]), the violation of charge symmetry in the 3 H and 3 Не mirror nuclei [4][5][6], the nuclearmatter effect on pions and their resonance states [7][8][9][10], and a comparison of the scattering of different particles (pions, kaons, protons, and electrons) on nuclei [11][12][13][14]. Quark degrees of freedom in pion scattering were taken into account within effective chiral field theory [7,15].…”

Comparative analysis of the pion-nucleus scattering within the microscopic Folding and the local Kisslinger type potentials

“…In the case of folding OP (solid red curves) we used the nuclear point-density-distributions (for centers of nucleons) in the form of a symmetrized fermi-function (4) with the radius R and diffuseness a parameters R = 3.134 fm and a = 0.477 fm for 28 Si, and R = 3.593 fm and a = 0.493 fm for 40 Ca (see [12]). As to the"in-medium" parameters σ, α, β of a πN scattering amplitude they have been fitted in [10] and [11], and the corresponding χ 2 magnitudes per one experimental point are presented in table 1 for the region of scattering angles up to 80 degrees. The "in-medium" effect is revealed more clearly when one compares the"in-medium" parameters to the respective parameters for the pion scattering on "free" nucleons done in [13].…”

“…T he second model of OP [4] corresponds to the eikonal phase of the Glauber high-energy approximation [5] and, in fact, becomes the folding integral of the πN amplitude and form factor of the nuclear density distribution function. For the pion-nucleus scattering this OP was applied in [6], and unlike the Glauber approach for the scattering amplitude where one uses integration along the straight line trajectory of motion, in our calculations we solve the Klein-Gordon relativistic wave equation and thus relativistic and distortion effects are accounted for exactly. For both OPs, we compare the calculated differential cross sections with experimental data and thus obtain forms of respective potentials to establish the meaningful regions of nuclei that reveal themselves in the pion scattering.…”

Analysis of inelastic pion-nucleus scattering within the microscopic optical potential and the in-medium effect on $\pi$n amplitude in nuclei

“…In analysis of the data on inelastic scattering of pions from nuclei we use the microscopic folding-like optical potential (OP) derived in [1] for elastic scattering. This OP has been successfully applied for elastic scattering of the K-and pi-mesons on nuclei [2], [3], [4], [5]. It is constructed as a folding integral of a nuclear density form factor and the pion-nucleon amplitude of scattering.…”