999 resultados para NN interaction


Relevância:

100.00% 100.00%

Publicador:

Resumo:

The subtracted kernel method is implemented recursively to solve scattering equations for the S-1(0) phase-shifts considering the leading and the next-to-leading order NN interaction.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We apply the subtractive renormalization method to the nucleon-nucleon interaction at Next-to-Next-to-Leading order (NNLO). Here we show the results for some uncoupled peripheral waves.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The aim of this work is to show how to renormalize the nucleon-nucleon interaction at next-to-next-to-leading order using a. systematic subtractive renormalization approach with multiple subtractions. As an example, we calculate the phase shifts for the partial waves with total angular momentum J = 2. The intermediate driving terms at each recursive step as well as the renormalized T-matrix are also shown. We conclude that our method is reliable for singular potentials such as the two-pion exchange and derivative contact interactions.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

In a simplest case we employ dimensional regularization method in order to evaluate the contribution of two pion exchanges to the NN interaction. The method allows one to treat the infinities of scattering amplitude in a way consistent with the symmetries of the theory.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

A renormalization scheme for the nucleon-nucleon (NN) interaction based on a subtracted T-matrix equation is proposed and applied to the one-pion-exchange potential supplemented by contact interactions. The singlet and triplet scattering lengths are given to fix the renormalized strengths of the contact interactions. With only one scaling parameter (μ), the results show an overall very good agreement with neutron-proton data, particularly for the observables related to the triplet channel. The agreement is qualitative in the 1 S0 channel. Between the low-energy NN observables we have examined, the mixing parameter of the 3S1-3D1 states is the most sensitive to the scale. The scheme is renormalization group invariant for μ → ∞. © 1999 Elsevier Science B.V. All rights reserved.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The deuteron binding energy and wave function are calculated by using the recently developed three-dimensional form of low-momentum nucleon-nucleon (NN) interaction. The homogeneous Lippmann-Schwinger equation is solved in momentum space by using the low-momentum two-body interaction, which is constructed from Malfliet-Tjon potential. The results for both, deuteron binding energy and wave function, obtained with low-momentum interaction, are compared with the corresponding results obtained with bare potential. © 2012 Springer-Verlag.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

We argue that the minimal chiral background for the two-pion exchange nucleon-nucleon (NN) interaction has nowadays a rather firm conceptual basis, which entitles it to become a standard ingredient of any modern potential. In order to facilitate applications, we present a parametrized version of a configuration space potential derived previously. We than use it to assess the phenomenological contents of some existing NN potentials.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

In 1998 a pilot experiment was carried out to study the helicity dependence of photoreaction cross sections using circularly polarized real photons on longitudinally polarized deuterons in a deuterated butanol target. The knowledge of these cross sections is required to test the validity of the Gerasimov-Drell-Hearn sum rule on the deuteron and the neutron. The focus of this thesis is on the results for the differential and total cross sections for the photodisintegration reaction for various photon energies in the range from 200 to 450 MeV using data taken with the detector system DAPHNE. The current understanding of the NN interaction as represented by the calculations by M. Schwamb could be confirmed within the given uncertainties. In addition, the detector DAPHNE has been prepared for the main experiment in 2003. The according work is presented together with results of the quality-test measurements of the renewed detector components.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We present ΛΛ correlation measurements in heavy-ion collisions for Au+Au collisions at sqrt[s_{NN}]=200  GeV using the STAR experiment at the Relativistic Heavy-Ion Collider. The Lednický-Lyuboshitz analytical model has been used to fit the data to obtain a source size, a scattering length and an effective range. Implications of the measurement of the ΛΛ correlation function and interaction parameters for dihyperon searches are discussed.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We present a systematic analysis of two-pion interferometry in Au+Au collisions at s(NN)=62.4 GeV and Cu+Cu collisions at s(NN)=62.4 and 200 GeV using the STAR detector at the Relativistic Heavy Ion Collider (RHIC). The multiplicity and transverse momentum dependences of the extracted correlation lengths (radii) are studied. The scaling with charged particle multiplicity of the apparent system volume at final interaction is studied for the RHIC energy domain. The multiplicity scaling of the measured correlation radii is found to be independent of colliding system and collision energy.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Interaction forces between protein inclusion bodies and an air bubble have been quantified using an atomic force microscope (AFM). The inclusion bodies were attached to the AFM tip by covalent bonds. Interaction forces measured in various buffer concentrations varied from 9.7 nN to 25.3 nN (+/- 4-11%) depending on pH. Hydrophobic forces provide a stronger contribution to overall interaction force than electrostatic double layer forces. It also appears that the ionic strength affects the interaction force in a complex way that cannot be directly predicted by DLVO theory. The effects of pH are significantly stronger for the inclusion body compared to the air bubble. This study provides fundamental information that will subsequently facilitate the rational design of flotation recovery system for inclusion bodies. It has also demonstrated the potential of AFM to facilitate the design of such processes from a practical viewpoint.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Delta isobar components in the nuclear many-body wave function are investigated for the deuteron, light nuclei (16O), and infinite nuclear matter within the framework of the coupled-cluster theory. The predictions derived for various realistic models of the baryon-baryon interaction are compared to each other. These include local (V28) and nonlocal meson exchange potentials (Bonn2000) but also a model recently derived by the Salamanca group accounting for quark degrees of freedom. The characteristic differences which are obtained for the NDelta and Delta Delta correlation functions are related to the approximation made in deriving the matrix elements for the baryon-baryon interaction.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We derive a NN*(1440) potential from a nonrelativistic quark-quark interaction and a quark cluster model for the baryons. By making use of the Born-Oppenheimer approximation, we examine quark Pauli correlations in detail. A comparison with the NN potential derived in the same framework is done. This makes it possible to emphasize the role of quark antisymmetry beyond baryon antisymmetry and to discuss the use of phenomenological NN*(1440) baryonic potentials.