Chronology of the three-body dissociation of 8He. (12th February 2019)

• Record Type: Journal Article
• Authors: Laurent, B; Marqués, F M; Angulo, C; Ashwood, N I; Borge, M J G; Bouchat, V; Catford, W N; Clarke, N M; Curtis, N; Freer, M; Hanappe, F; Kinnard, V; Labiche, M; Materna, T; McEwan, P; Nilsson, T; Ninane, A; Normand, G; Orr, N A; Pain, S D; Prokhorova, E; Stuttgé, L; Timis, C
• Is Part Of: Journal of physics. Volume 46:Number 3(2019)
• Publication Date: 2019-02-12
• Subjects: neutron correlations -- three-body decays -- halo nuclei; Nuclear physics -- Periodicals; Particles (Nuclear physics) -- Periodicals; Physique nucléaire -- Périodiques; Particules (Physique nucléaire) -- Périodiques; Kernfysica; Elementaire deeltjes; 539.7
• DOI: 10.1088/1361-6471/ab02c3
• Languages: English
• ISSNs: 0954-3899

Abstract

Abstract: The space and time configurations of the dissociation of 8 He into 6 He+ n + n, on C and Pb targets, have been explored simultaneously for the first time. The final-state interactions in the n - n and 6 He- n channels are successfully described within a model that considers independent emission of neutrons from a Gaussian volume with a given lifetime. The dissociation on C target exhibits a dominant sequential decay through the ground state of 7 He, consistent with neutrons being emitted from a Gaussian volume of r nn rms = 7.3 ± 0.6 fm with a n-n delay in the sequential channel of 1400 ± 400 fm/ c, in agreement with the lifetime of 7 He. The lower-statistics data on Pb target correspond mainly to direct breakup, and are well described using the n - n volume measured, without any n -n delay. The validity of the phenomenological model used is discussed.