Few-Body Systems

, 59:54 | Cite as

Triple \(\alpha \) Resonances and Possible Link to the Efimov Trimers

  • A. TuminoEmail author
  • A Bonasera
  • G. Giuliani
  • M. Lattuada
  • M. Milin
  • R. G. Pizzone
  • C. Spitaleri
  • S. Tudisco
Part of the following topical collections:
  1. Critical Stability 2017


The basic condition for Efimov states is the existence of resonant two-body forces. A system of three particles with resonant two-body interactions may form bound states, the so called Efimov trimers, even when any two of the particles are unable to bind. Inspired by this idea we have analysed a set of data from the \(^6\hbox {Li}+^6\hbox {Li}\rightarrow 3 \alpha \) reaction measured in a kinematically complete experiment at 3.1 MeV of beam energy, corresponding to 29.6 MeV of excitation energy in \(^{12}\hbox {C}\), with the characteristic that the 3\(\alpha \) channel is fed by three \(^8\hbox {Be}\) states in the same event. A strong enhancement in the \(\alpha \)\(\alpha \) coincidence yield is experienced for these events. Evidence of three \(^8\hbox {Be}\) levels within the same 3\(\alpha \) event suggests that one particle is exchanged between the other two. According to quantum mechanics, this is a condition for Efimov states to occur and for which no observation exists yet in nuclei. The hyperspherical formalism for the low-energy three-body problem has been applied to point out the 3\(\alpha \) particle correlation.


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Copyright information

© Springer-Verlag GmbH Austria, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Facoltá di Ingegneria e ArchitetturaUniversità degli Studi di Enna “Kore”EnnaItaly
  2. 2.INFN-Laboratori Nazionali del SudCataniaItaly
  3. 3.Cyclotron InstituteTexas A&M UniversityTXUSA
  4. 4.Dipartimento di Fisica e AstronomiaUniversità di CataniaCataniaItaly
  5. 5.Faculty of ScienceUniversity of ZagrebZagrebCroatia

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