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arXiv · 1112.4529

Evidence for 6ΛH

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·B. Dalena·F. De Mori·G. D'Erasmo·F. L. Fabbri·A. Feliciello·A. Filippi·E. M. Fiore·A. Fontana·H. Fujioka·P. Genova·P. Gianotti·N. Grion·V. Lucherini·S. Marcello·N. Mirfakhrai·F. Moia·O. Morra·T. Nagae·H. Outa·A. Pantaleo·V. Paticchio·S. Piano·R. Rui·G. Simonetti·R. Wheadon·A. Zenoni·A. Gal
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Abstract

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 \rightarrow 6 H+π+ production reaction followed by 6ΛH \rightarrow 6He + π- weak decay. The production rate of 6ΛH undergoing this two-body π- decay is determined to be (2.9\pm2.0)\cdot10-6/K-. Its binding energy, evaluated jointly from production and decay, is BΛ(6ΛH) = (4.0\pm1.1) MeV with respect to 5H+Λ. A systematic difference of (0.98 \pm 0.74) MeV between BΛ values derived separately from decay and from production is tentatively assigned to the 6ΛH 0+g.s. \rightarrow 1+ excitation.

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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, B. Dalena, F. De Mori, G. D'Erasmo, F. L. Fabbri, A. Feliciello, A. Filippi, E. M. Fiore, A. Fontana, H. Fujioka, P. Genova, P. Gianotti, N. Grion, V. Lucherini, S. Marcello, N. Mirfakhrai, F. Moia, O. Morra, T. Nagae, H. Outa, A. Pantaleo, V. Paticchio, S. Piano, R. Rui, G. Simonetti, R. Wheadon, A. Zenoni, A. Gal. 2011-12-19. Evidence for 6ΛH. https://doi.org/10.1103/physrevlett.108.042501

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