Probing the deuteron structure at small NN distances by antiproton-deuteron annihilation

The annihilation p̄d→2π−π+p at rest with the proton momentum in the final state ≥400 MeV/c is analysed. Assuming that the deuteron wave function can be represented by the Fockʹs column consisting of different possible states (NN, NN∗, ΔΔ, NNπ,…) some enhancement in the distribution over the invariant mass of the π−π− system in the mass region 1.4–1.5(GeV/c2) is predicted. This can be caused by the possible existence of a Δ−Δ component in deuteron. Using this prediction and new experimental data of the OBELIX collaboration (LEAR, CERN) one can estimate the upper limit for this exotic state of the deuteron.