Résumé du preprint Irfu-15-71

Irfu-15-71
New findings on structure and production of 10He from 11Li with (d,3He) reaction.
A. Matta, D. Beaumel, H. Otsu, V. Lapoux, N. K. Timofeyuk, N. Aoi, M. Assié, H. Baba, S. Boissinot, R.J. Chen, F. Delaunay, N. de Sereville, S. Franchoo, P. Gangnant, J. Gibelin, F. Hammache, Ch. Houarner, N. Imai, N. Kobayashi, T. Kubo, Y. Kondo, Y. Kawada, L.H. Khiem, M. Kurata-Nishimura, E. A. Kuzmin, J. Lee, J.F. Libin, T. Motobayashi, T. Nakamura, L. Nalpas, E. Yu. Nikolskii, A. Obertelli, E. C. Pollacco, E. Rindel, Ph. Rosier, F. Saillant, T. Sako, H. Sakurai, A. M. Sánchez-Benítez, J-A. Scarpaci, I. Stefan, D. Suzuki, K. Takahashi, M. Takechi, S. Takeuchi, H .Wang, R. Wolski, and K. Yoneda
We present the first missing mass spectrum of the unbound nucleus 10He, measured at RIKEN using the 11Li(d,3He) reaction at 50A MeV. 10He is believed to be a three-body 8He+n+n resonance beyond the limit of nuclear binding. Our observation of a new decay branch, 6He+4n , and of a puzzling reduction of the 11Li(d,3He)10He cross section challenges this view. Moreover, our experiment shows a new trend in the evolution of the proton spectroscopic strength in Li isotopes deduced from the comparison of the (d,3He) cross sections on Li 7,8,9,11 with theoretical predictions. We discuss new questions about physics beyond the limits of nuclear existence raised by these findings.