1. Chronology of the three-body dissociation of $^8$He
- Author
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Thomas Nilsson, N. Curtis, Alain Ninane, L. Stuttge, V. Bouchat, Martin Freer, W. N. Catford, Thomas Materna, F. M. Marqués, C. N. Timis, Steven Pain, V. Kinnard, P. McEwan, María José García Borge, B. Laurent, M. Labiche, E. V. Prokhorova, N. A. Orr, C. Angulo, N. M. Clarke, N. I. Ashwood, Francis Hanappe, G. Normand, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Nuclear and High Energy Physics ,nucl-th ,Nuclear Theory ,[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th] ,Gaussian ,FOS: Physical sciences ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,nucl-ex ,01 natural sciences ,Dissociation (chemistry) ,Nuclear Theory (nucl-th) ,symbols.namesake ,0103 physical sciences ,Phenomenological model ,Nuclear Physics - Experiment ,Neutron ,Nuclear Experiment (nucl-ex) ,010306 general physics ,Nuclear Experiment ,Nuclear theory ,Physics ,Spacetime ,010308 nuclear & particles physics ,Breakup ,Nuclear Physics - Theory ,symbols ,Atomic physics ,Ground state - Abstract
7 pags., 5 figs., 1 app., The space and time configurations of the dissociation of He into 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 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 He, consistent with neutrons being emitted from a Gaussian volume of fm with a n-n delay in the sequential channel of 1400 400 fm/c, in agreement with the lifetime of 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., The support provided by the technical staff of LPC and the LISE crew is gratefully acknowledged, as are the efforts of the GANIL cyclotron operation team for providing the primary beam. We also wish to express our appreciation for the vital contributions made by our late colleague and friend Jean-Marc Gautier to all the CHARISSA+DEMON experiments undertaken by our collaboration.
- Published
- 2019