Evidence for Heavy HyperhydrogenHΛ6
M. Agnello, L. Benussi, M. Bertani, H. C. Bhang, G. Bonomi, E. Botta, M. Bregant, T. Bressani, S. Bufalino, L. Busso, D. Calvo, P. Camerini
Physical Review Letters
Evidence for the neutron-rich hypernucleus 6ΛH is presented from the FINUDA experiment at DAΦNE, Frascati, studying (π+, π-) pairs in coincidence from the K- +6Li → 6 H+π+ production reaction followed by 6ΛH → 6He + π- weak decay. The production rate of 6ΛH undergoing this two-body π- decay is determined to be (2.9±2.0)·10-6/K-. Its binding energy, evaluated jointly from production and decay, is BΛ(6ΛH) = (4.0±1.1) MeV with respect to 5H+Λ. A systematic difference of (0.98 ± 0.74) MeV between
... values derived separately from decay and from production is tentatively assigned to the 6ΛH 0+g.s. → 1+ excitation.