ar X iv : n uc l - th / 0 11 10 81 v 1 2 8 N ov 2 00 1 A Possibility to Observe Short - Range NN Properties in the Deuteron Breakup pd → ppn

Quasi-binary reaction of the deuteron breakup p+d → (pp)+n with the final proton-proton pair (pp) in the 1 S 0 state is analyzed at initial energies 0.5 − 2 GeV in the kinematics of backward elastic pd-scattering pd → dp. On the basis of the main mechanisms of the pd → dp process, including initial and final state interaction, we show that unpolarized cross section and spin observables of this reaction exhibit important properties of the half-off-shell pp(1 S 0)-scattering amplitude, which are relevant to the nucleon-nucleon interaction at short distances. The short-range structure of the lightest nuclei is related to fundamental problems of the theory of strong interactions. At present the main task consists in a clear experimental observation of this structure and determination to what limiting values of the intrinsic nucleon momenta q the traditional description of nuclei in terms of nucleons is valid. In the framework of the impulse approximation (IA), available inclusive experimental data on spin averaged cross section for deuteron disintegration d p → p(0 •) X, d 12 C→ p(0 •) X (see [1,2] and references therein) are compatible with the realistic deuteron wave functions at low internal momenta q < 0.3 GeV/c only. At higher momenta a systematic deviation from the IA is observed [3]. This disagreement is very strong for the tensor analyzing power T 20 of these reactions. On the contrary, the recent JLab data on T 20 in the elastic ed-scattering [4] demonstrate that the similar impulse approximation with standard wave function, such as RSC [5], Paris [6] or Bonn [7], is in fair agreement with the experiment over the interval of transferred momenta Q 2 = 0 − 1.7 (GeV/c) 2 , i.e. for the same internal momenta q ∼ Q/2 ∼ 0.7 GeV/c as probed in pd-interaction. On the whole, such difference between the ed-and pd-interactions can be attributed to a presence of specific for pd-collisions mechanisms, in particular, to the exotic like N *-exchanges in the u-channel [8,9] or three-baryon resonances in the s-channel [10]. The deviation from the IA in exclusive data on the reaction p + d → p + n + p can be explained in part by rescatterings in the final state [11]. Other ordinary mechanisms like double pN-scattering with excita-tion (and de-excitation) of nucleon isobars (∆, N *) in the intermediate states can give a large contribution also. The latter mechanisms are …