Advanced

Strong Neutron Pairing in core+4n Nuclei

Revel, A.; Marqués, F. M.; Sorlin, O.; Aumann, T.; Caesar, C.; Holl, M.; Panin, V.; Vandebrouck, M.; Wamers, F. and Alvarez-Pol, H., et al. (2018) In Physical Review Letters 120(15).
Abstract

The emission of neutron pairs from the neutron-rich N=12 isotones C18 and O20 has been studied by high-energy nucleon knockout from N19 and O21 secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay N19(-1p)C18∗→C16+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a C14 core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay O21(-1n)O20∗→O18+n+n, attributed to its formation through the knockout of... (More)

The emission of neutron pairs from the neutron-rich N=12 isotones C18 and O20 has been studied by high-energy nucleon knockout from N19 and O21 secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay N19(-1p)C18∗→C16+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a C14 core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay O21(-1n)O20∗→O18+n+n, attributed to its formation through the knockout of a deeply bound neutron that breaks the O16 core and reduces the number of pairs.

(Less)
Please use this url to cite or link to this publication:
@article{793ff7c0-850b-4298-8099-46c01b582f5e,
  abstract     = {<p>The emission of neutron pairs from the neutron-rich N=12 isotones C18 and O20 has been studied by high-energy nucleon knockout from N19 and O21 secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay N19(-1p)C18∗→C16+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a C14 core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay O21(-1n)O20∗→O18+n+n, attributed to its formation through the knockout of a deeply bound neutron that breaks the O16 core and reduces the number of pairs.</p>},
  articleno    = {152504},
  author       = {Revel, A. and Marqués, F. M. and Sorlin, O. and Aumann, T. and Caesar, C. and Holl, M. and Panin, V. and Vandebrouck, M. and Wamers, F. and Alvarez-Pol, H. and Atar, L. and Avdeichikov, V. and Beceiro-Novo, S. and Bemmerer, D. and Benlliure, J. and Bertulani, C. A. and Boillos, J. M. and Boretzky, K. and Borge, M. J.G. and Caamaño, M. and Casarejos, E. and Catford, W. N. and Cederkäll, J. and Chartier, M. and Chulkov, L. and Cortina-Gil, D. and Cravo, E. and Crespo, R. and Datta Pramanik, U. and Díaz Fernández, P. and Dillmann, I. and Elekes, Z. and Enders, J. and Ershova, O. and Estradé, A. and Farinon, F. and Fraile, L. M. and Freer, M. and Galaviz, D. and Geissel, H. and Gernhäuser, R. and Golubev, P. and Göbel, K. and Hagdahl, J. and Heftrich, T. and Heil, M. and Heine, M. and Heinz, A. and Henriques, A. and Knyazev, A. and , },
  issn         = {0031-9007},
  language     = {eng},
  month        = {04},
  number       = {15},
  publisher    = {American Physical Society},
  series       = {Physical Review Letters},
  title        = {Strong Neutron Pairing in core+4n Nuclei},
  url          = {http://dx.doi.org/10.1103/PhysRevLett.120.152504},
  volume       = {120},
  year         = {2018},
}