English

Comment on Neutron-Proton Spin-Correlation Parameter A_{ZZ} at 68 Mev

Nuclear Theory 2009-10-22 v1

Abstract

We present two arguments indicating that the large value for the ϵ1\epsilon_1 mixing parameter at 50 MeV, which the Basel group extracted from their recent AzzA_{zz} measurement, may be incorrect. First, there are nucleon-nucleon (NN) potentials which predict the ϵ1\epsilon_1 at 50 MeV substantially below the Basel value and reproduce the Basel AzzA_{zz} data accurately. Second, the large value for ϵ1\epsilon_1 at 50 MeV proposed by the Basel group can only be explained by a model for the NN interaction which is very unrealistic (no ρ\rho-meson and essentially a point-like πNN\pi NN vertex) and overpredicts the ϵ1\epsilon_1 in the energy range where it is well determined (150--500 MeV) by a factor of two.

Keywords

Cite

@article{arxiv.nucl-th/9303022,
  title  = {Comment on Neutron-Proton Spin-Correlation Parameter A_{ZZ} at 68 Mev},
  author = {R. Machleidt and I. Slaus},
  journal= {arXiv preprint arXiv:nucl-th/9303022},
  year   = {2009}
}

Comments

6 pages text (LaTex) and 2 figures (paper, will be faxed upon request), UI-NTH-9303

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