https://doi.org/10.1140/epja/i2019-12756-8
Regular Article - Theoretical Physics
Efimov universality with Coulomb interaction
1
Institut für Kernphysik, Technische Universität Darmstadt, 64289, Darmstadt, Germany
2
Nishina Center, RIKEN, 351-0198, Saitama, Japan
3
ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung, 64291, Darmstadt, Germany
4
Department of Physics, Kyushu University, 819-0395, Fukuoka, Japan
* e-mail: schmickler@theorie.ikp.physik.tu-darmstadt.de
Received:
16
January
2019
Accepted:
15
April
2019
Published online:
30
May
2019
The universal properties of charged particles are modified by the presence of a long-range Coulomb interaction. We investigate the modification of Efimov universality as a function of the Coulomb strength using the Gaussian Expansion Method. The resonant short-range interaction is described by Gaussian potentials to which a Coulomb potential is added. We calculate binding energies and root mean square radii for the three- and four-body systems of charged particles and present our results in a generalised Efimov plot. We find that universal features can still be discerned for weak Coulomb interaction, but break down for strong Coulomb interaction. The maximum root mean square radius of the system decreases as the strength of the Coulomb interaction is increased and the probability distributions of the states become more concentrated inside the Coulomb barrier. As an example, we apply our universal model to nuclei with an 
cluster substructure. Our results point to strong non-universal contributions in that sector.
© Società Italiana di Fisica / Springer-Verlag GmbH Germany, part of Springer Nature, 2019
