Decay Pattern of Pygmy States Observed in Neutron-Rich 26 Ne
Abstract
Coulomb excitation of the exotic neutron-rich nucleus Ne26 on a Pb208 target was measured at 58 MeV/u in order to search for low-lying E1 strength above the neutron emission threshold. This radioactive beam experiment was carried out at the RIKEN Accelerator Research Facility. Using the invariant mass method in the Ne25+n channel, we observe a sizable amount of E1 strength between 6 and 10 MeV excitation energy. By performing a multipole decomposition of the differential cross section, a reduced dipole transition probability of B(E1)=0.49+-0.16e2fm2 is deduced, corresponding to 4.9+-1.6% of the Thomas-Reiche-Kuhn sum rule. For the first time, the decay pattern of low-lying strength in a neutron-rich nucleus is measured. The extracted decay pattern is not consistent with several mean-field theory descriptions of the pygmy states.
Keywords
Cite
@article{arxiv.2307.05079,
title = {Decay Pattern of Pygmy States Observed in Neutron-Rich 26 Ne},
author = {J. Gibelin and D. Beaumel and T. Motobayashi and Y. Blumenfeld and N. Aoi and H. Baba and Z. Elekes and S. Fortier and N. Frascaria and N. Fukuda and T. Gomi and K. Ishikawa and Y. Kondo and T. Kubo and V. Lima and T. Nakamura and A. Saito and Y. Satou and J. -A. Scarpaci and E. Takeshita and S. Takeuchi and T. Teranishi and Y. Togano and A. M. Vinodkumar and Y. Yanagisawa and K. Yoshida},
journal= {arXiv preprint arXiv:2307.05079},
year = {2023}
}
Comments
arXiv admin note: text overlap with arXiv:0705.1753