| Autor: |
Wei Zhang, Bo Cederwall, Ozge AKTAS, Xiaoyu Liu, Aysegül Ertoprak, Ayse Nyberg, Kalle Auranen, Betool Alayed, Hussam Badran, Helen Boston, Maria Doncel, Ulrika Forsberg, Tuomas Grahn, Paul Greenlees, Song GUO, Jacob Heery, Joshua Hilton, David Jenkins, Rauno Julin, Sakari Juutinen, Minna Luoma, Olavi Neuvonen, Joonas Ojala, Robert Page, Janne Pakarinen, Edward Paul, Costel Petrache, Panu Rahkila, Panu Ruotsalainen, Mikael Sandzelius, Jan Sarén, Stuart Szwec, Holly Tann, Juha Uusitalo, Robert Wadsworth |
| Rok vydání: |
2022 |
| Předmět: |
|
| Popis: |
The discovery of the new proton emitter $^{116}_{~57}$La$_{59}$, 23 neutrons away from the only stable La isotope, $^{139}_{~57}$La$_{82}$, is reported. The $^{116}$La nuclei were synthesised in the fusion-evaporation reaction $^{58}$Ni($^{64}$Zn, p4n)$^{116}$La and identified via their proton radioactivity using the MARA mass spectrometer and the silicon detectors placed at its focal plane. Comparisons of the measured proton energy ($E_{p} = 718 \pm 9 $ keV) and half-life ($T_{1/2} = 50 \pm 22$ ms) with values calculated using %microscopic nuclear barrier penetration theory the Universal Decay Law approach indicate that the proton is emitted with an orbital angular momentum $l=2$ and that its emission probability is enhanced relative to its closest, less exotic, odd-even lanthanum isotope ($^{117}_{~57}$La$_{60}$) while the proton-emission $Q$-value is lower. We propose this to be a signature for the presence of strong neutron-proton pair correlations in this exotic, neutron deficient system. The observations of $\gamma$ decays from isomeric states in $^{116}$La and $^{117}$La are also reported. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
