Direct observation of the glue pairing the halo of the nucleus 11Li

With the help of a unified nuclear structure–direct reaction heory we analyze the reaction 1H(11Li,9Li) 3H. The two halo neutrons are correlated through the bare and the induced (medium polarization) pairing interaction. By considering all dominant reaction processes leading to t he population of the 1 /2 (2.69 MeV) first excited state of9Li, namely multistep transfer (successive, simultaneous a nd non–orthogonality), breakup and inelastic channels, it is possible to show that the experiment provide s, for the first time in nuclear physics, direct evidence of phonon mediated pairing. PACS: 25.40.Hs, 25.70.Hi, 74.20.Fg, 74.50. +r