NNcore interactions and differential cross sections from one gluon exchange

Abstract

We derive nonstrange baryon-baryon scattering amplitudes in the nonrelativistic quark model using the "quark Born diagram" formalism. This approach describes the scattering as a single interaction, here the one-gluon-exchange (OGE) spin-spin term followed by constituent interchange, with external nonrelativistic baryon wave functions attached to the scattering diagrams to incorporate higher-twist wave-function effects. The short-range repulsive core in the NN interaction has previously been attributed to this spin-spin interaction in the literature; we find that these perturbative constituent-interchange diagrams do indeed predict repulsive interactions in all I, S channels of the nucleon-nucleon system, and we compare our results for the equivalent short-range potentials to the core potentials found by other authors using nonperturbative methods. We also apply our perturbative techniques to the NA and AA systems: Some AA channels are found to have attractive core potentials and may accommodate "molecular" bound states near threshold. Finally we use our Born formalism to calculate the NN differential cross section, which we compare with experimental results for unpolarized proton-proton elastic scattering. We Gnd that several familiar features of the experimental differential cross section are reproduced by our Born-order result.PACS number(s): 21.30. +y, 24. 10.i

Cross sections forπ- andρ-induced dissociation ofJ/ψandψWong1, Swanson2, Barnes3 2000Phys. Rev. CSelf Cite10761373View full textAdd to dashboardCite

“…The destructive interference between transfer and capture diagrams with spinindependent forces (color Coulomb and confinement) has been noted previously (see, for example, Refs. [21,22] and references cited in [25]). This interference explains the wellknown spin-spin hyperfine dominance in light hadron scattering in channels such as I = 2 ππ and NN.…”

“…[21]. This method has previously been applied successfully to the closely related no-annihilation scattering channels I = 2 ππ [21], I = 3/2 Kπ [23], I = 0, 1 S-wave KN scattering [24] and the short-range repulsive NN interaction [25]. Following Ref.…”

Chiral Condensate and Mott–Anderson Freeze-Out

“…When interpreted in terms of hadron-hadron scattering phase shifts (see, e.g., Refs. [34,[54][55][56] for early examples of quark exchange contributions) the quark substructure effects could be accounted for by a Beth-Uhlenbeck type generalization of the thermodynamical potential [42,57,58]. It is expected, that besides changes in the hadron wave functions, the masses of baryons shall get reduced at high densities whereas the masses of mesons could increase toward the chiral restoration.…”

Nuclear Collective Motion

“…In spite of this, the conventional shell-model calculations employing realistic NNinteractions 42,43] That the conventional shell model fails at short distances, due to the presence of short-range correlations, has been known for quite some time. Recently, 16 O(e,e 0 pp) 14 C t wo-proton knock-out data 56,57] o ered an opportunity t o study one-and two-body currents and to discriminate between long-range and short-range correlations 58]. Such studies are extremely important for understanding in-medium e ects in nuclear matter.…”