Quark degrees of freedom in the deuteron and their testing in nucleon-deuteron scattering

The discrepancies between theoretical predictions and experimental data for nucleon-deuteron scattering at high momentum transfers are usually attributed to the three-nucleon force effects but inclusion of 3N forces (of conventional type) in exact Faddeev calculations helps to improve the agreement with the data only partially. Alternatively, the short-range part of 2N interaction (manifesting itself in processes with large transferred momenta) may be modified by incorporating quark degrees of freedom. Such a microscopic NN-force model - the dressed bag model - was proposed by the Moscow-Tuebingen group and is based on the production of an intermediate 6q bag dressed by a strong σ field. It is demonstrated that taking into account the formation of an intermediate 6q bag leads to a noticeable enhancement of the deuteron wave function in the high-momentum region. Our preliminary calculations performed within the dressed bag model show that the suggested mechanism of the short-range NN interaction gives significant contribution to the nucleon-deuteron scattering at high momentum transfers both through 2N and 3N forces.