A1 Journal article (refereed)
Observation of the proton emitter 116,57La59 (2022)


Zhang, W., Cederwall, B., Aktas, Ö., Liu, X., Ertoprak, A., Nyberg, A., Auranen, K., Alayed, B., Badran, H., Boston, H., Doncel, M., Forsberg, U., Grahn, T., Greenlees, P. T., Guo, S., Heery, J., Hilton, J., Jenkins, D., Julin, R., . . . Wadsworth, R. (2022). Observation of the proton emitter 116,57La59. Communications Physics, 5, Article 285. https://doi.org/10.1038/s42005-022-01069-w


JYU authors or editors


Publication details

All authors or editorsZhang, Wei; Cederwall, Bo; Aktas, Özge; Liu, Xiaoyu; Ertoprak, Aysegül; Nyberg, Ayse; Auranen, Kalle; Alayed, Betool; Badran, Hussam; Boston, Helen; et al.

Journal or seriesCommunications Physics

eISSN2399-3650

Publication year2022

Publication date14/11/2022

Volume5

Article number285

PublisherNature Publishing Group

Publication countryUnited Kingdom

Publication languageEnglish

DOIhttps://doi.org/10.1038/s42005-022-01069-w

Publication open accessOpenly available

Publication channel open accessOpen Access channel

Publication is parallel published (JYX)https://jyx.jyu.fi/handle/123456789/84039


Abstract

The quantum tunneling and emission of a single constituent nucleon provide a beautifully simple and unique window into the complex properties of atomic nuclei at the extreme edge of nuclear existence. In particular, for odd-odd proton emitting nuclides, the associated decay energy and partial half-life can be used to probe the correlations between the valence neutrons and protons which have been theoretically predicted to favour a new type of nuclear superfluidity, isoscalar neutron-proton pairing, for which the experimental “smoking gun" remains elusive. In the present work, proton emission from the lanthanum isotope 11657La59, 23 neutrons away from the only stable isotope 13957La82, is reported. 116La nuclei were synthesised in the fusion-evaporation reaction 58Ni(64Zn, p5n)116La and identified via their proton radioactivity using the mass spectrometer MARA (Mass Analysing Recoil Apparatus) and the silicon detectors placed at its focal plane. Comparisons of the measured proton energy (Ep = 718 ± 9 keV) and half-life (T1/2 = 50 ± 22 ms) with values calculated using 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 (11757La60) while the proton-emission Q-value is lower. We propose this to be a possible signature for the presence of strong neutron-proton pair correlations in this exotic, neutron deficient system. The observations of γ decays from isomeric states in 116La and 117La are also reported.


Keywordsnuclear physicsisotopesemission (physics)protonsmass spectrometry


Contributing organizations


Ministry reportingYes

Reporting Year2022

JUFO rating1


Last updated on 2024-10-03 at 19:36