arXiv:2310.04736·v5·Nuclear Experiment
Candidate toroidal electric dipole mode in the spherical nucleus Ni
P. von Neumann-Cosel (1) · V.O. Nesterenko (2,3) · I. Brandherm (1) · P.I. Vishnevskiy (2,4) · P.-G. Reinhard (5) · J. Kvasil (6) · H. Matsubara (7,8) · A. Repko (9) · A. Richter (1) · M. Scheck (10,11) · A. Tamii (7) ((1) Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany, (2) Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Russia, (3) State University "Dubna", Dubna, Moscow region, Russia, (4) Institute of Nuclear Physics Almaty, Almaty Region, Kazakhstan, (5) Institut für Theoretische Physik II, Universität Erlangen, Erlangen, Germany, (6) Institute of Particle and Nuclear Physics, Charles University, Praha, Czech Republic, (7) Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka, Japan, (8) Faculty of Radiological Technology, Fujita Health University, Aichi, Japan, (9) Institute of Physics, Slovak Academy of Sciences, Bratislava, Slovakia, (10) School of Computing, Engineering, and Physical Sciences, University of the West of Scotland, Paisley, United Kingdom, (11) Scottish Universities Physics Alliance, United Kingdom)
Abstract
Dipole toroidal modes appear in many fields of physics. In nuclei, such a mode was predicted more than 50 years ago, but clear experimental evidence was lacking so far. Using a combination of high-resolution inelastic scattering experiments with photons, electrons and protons, we identify for the first time candidates for toroidal dipole excitations in the nucleus Ni and demonstrate that transverse electron scattering form factors represent a relevant experimental observable to prove their nature.
Comments: 13 pages, 8 figures