Effects of Deuteron Polarization in γd → pn and Dibaryon Resonances

Abstract

As is known, QCD predicts the existence of six-quark systems, which can manifest themselves as dibaryon resonances (DR). An unambiguous evidence for the DR is needed for several reasons. The deuteron photodisintegration γd → pn may have the following advantages over the reactions pp → pp, π ⁺d → pp, π ⁺d → π ⁺d, γd → dπ°. (i) In these reactions the pseudoresonances induced by NN^* — systems exist. Mainly, the pseudoresonances are related to the ΔN — system, but it cannot contribute to the isoscalar channel which is present in γd → pn and is not in other reactions. (ii) Excitation of the state with certain JP and the isospin I is determined by several pax= tial (or multipole) amplitudes in γd → pn. The comparison of the relations between the experimental amplitudes with the results of quark and pseudoresonance models can also contribute to the solution of the DR problem.