Nonlocal nucleon-nucleus interactions in (d,p) reactions: Role of the deuteron D state

Traditional (d; p) reaction models use local optical model potentials to represent the deuterontarget interaction. Within such models, the deuteron d-state contributes little to di�erential cross sections, as local potentials are only sensitive to low n-p relative momenta. However, recent work by Timofeyuk and Johnson, that includes the inherent nonlocality of the nucleontarget optical model potentials, suggests this is not true of nonlocal models which include deuteron breakup. This study showed that nonlocal deuteron-target potentials, found with a pure s-state deuteron, are infl uenced by large n-p relative momenta. The d-state can dominate the deuteron wavefunction at high momenta, suggesting d-state e�ects could be signi�cant in nonlocal reaction calculations. This work incorporates the d- state into deuteron-target potentials, in the presence of nonlocal nucleon-target interactions and breakup. This is found using energy independent nonlocal nucleon-target optical model potentials of the Perey-Buck type. Deuteron channel distorted waves can then be found and used to calculate di�erential cross sections. The proton channel is constructed in the same manner. It is shown that the d-state e�ects from the central part of the deuteron-target potentials signi�cantly alter calculated di�erential cross sections, when compared to nonlocal pure s-state calculations. The d-state also produces a tensor component of the deuteron-target potential, but this has negligible e�ects on cross section calculations. The choice of nucleon-nucleon potential, used to construct the deuteron wavefunction, is also investigated. It is shown that, within this works approach, calculated di�erential cross sections are sensitive to this choice. This is because the resulting wavefunctions have di�erent high momentum behaviors. This sensitivity is shown to be enhanced if the �nal state of the transfered neutron has a large separation energy. This work concludes that in nonlocal (d; p) reaction models, which include break-up e�ects, the deuteron d-state gives a signi�cant contribution to the deuteron-target potentials. The inclusion of nucleon-nucleus nonlocality in the deuteron-target potentials has produced sensitivity to the high momentum components of the deuteron wavefunction, where the d-state can dominate. The high momentum structure of the deuteron wavefunction di�ers between N-N models. As such, di�erential cross sections from this works approach can signi�cantly change depending on the choice of deuteron wavefunction.