Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userRelativistic multirank interaction kernels of the neutron-proton system
111
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The multirank separable kernels of the neutron-proton interaction for uncoupled $S$ and $P$ partial waves (with the total angular momentum $J$=0,1) are proposed. Two different methods of a relativistic generalization of initially nonrelativistic form factors parametrizing the kernel are considered. Using the constructed kernels the experimental data for phase shifts in the elastic neutron-proton scattering for the laboratory energy up to 3 GeV and low-energy parameters are described. The comparison of our results with other model calculations are presented.
rate research
Read More
Within a covariant Bethe-Salpeter approach, the relativistic complex separable neutron-proton interaction kernel is proposed. The uncoupled partial-wave states with the total angular momentum $J$=0,1 are considered. The multirank separable potentials elaborated earlier are real-valued and, therefore, enable to describe the elastic part (phase shifts, low-energy parameters, etc.) of the scattering only. The description of the inelasticity parameter comes out of the imaginary part introduced into them. To obtain parameters of the complex potentials the elastic neutron-proton scattering experimental data up to 3 GeV are used. A signal of dybaryon resonances in the $^3P_0^+$ partial-wave state is discussed.
Within a covariant Bethe-Salpeter approach a rank-six separable neutron-proton interaction kernel for the triplet coupled $^3S_1$-$^3D_1$ partial-wave state is constructed. Two different methods of a relativistic generalization of initially nonrelativistic form factors parametrizing the kernel are considered. The model parameters are determined by fitting the elastic $^3S_1$ and $^3D_1$ phase shifts and the triplet scattering length as well as the asymptotic $D/S$ ratio of the deuteron wave functions and the deuteron binding energy. The $D$-state probability constraints 4-7% are taken into account. The deuteron magnetic moment is calculated. The half-off-shell properties are further demonstrated by the Noyes-Kowalski functions. The first test of the constructed kernel is performed by calculating the deuteron electrodisintegration at three different kinematic conditions.
92 -
S.G. Bondarenko
, V.V. Burov
, E.P. Rogochaya (JINR - Joint Instituten for Nuclear Research
2011
Within a covariant Bethe-Salpeter approach the relativistic complex separable kernel of the neutron-proton interaction for the coupled $^3S_1^+$-$^3D_1^+$ partial-wave state is constructed. The rank-six separable potential elaborated earlier is real-valued, and therefore makes it possible to describe only the elastic part (phase shifts, low-energy parameters, deuteron properties, etc.) of the elastic neutron-proton scattering. The description of the inelasticity parameter comes out of the imaginary part introduced intthe potential. The complex potential parameters are obtained using the available elastic neutron-proton scattering experimental data up to 1.1 GeV.
The odd-odd nucleus 210Bi is studied within the framework of the shell model using effective two-body matrix elements derived from the CD-Bonn nucleon-nucleon potential. The experimental energies of the proton-neutron multiplet ph9/2 ng9/2 are remarkably well reproduced by the theory, which accounts for the 1- state being the ground state instead of the 0- predicted by the Nordheim strong coupling rule. It is shown that the core-polarization effects are crucial to produce this inversion. The similarity between neutron-proton multiplets in the 132Sn and 208Pb regions is discussed in connection with the effective interaction.
We highlight Hermiticity issues in bound-state equations whose kernels are subject to a highly asymmetric mass and momentum distribution and whose eigenvalue spectrum becomes complex for radially excited states. We trace back the presence of imaginary components in the eigenvalues and wave functions to truncation artifacts and suggest how they can be eliminated in the case of charmed mesons. The solutions of the gap equation in the complex plane, which play a crucial role in the analytic structure of the Bethe-Salpeter kernel, are discussed for several interaction models and qualitatively and quantitatively compared to analytic continuations by means of complex-conjugate pole models fitted to real solutions.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
