Detailed structure of Sn 131 populated in the β decay of isomerically purified in 131 states

TY - JOUR

T1 - Detailed structure of Sn 131 populated in the β decay of isomerically purified in 131 states

AU - IDS and IGISOL Collaboration

AU - Benito, J.

AU - Fraile, L. M.

AU - Korgul, A.

AU - Piersa-Siłkowska, M.

AU - Jaries, A.

AU - Stryjczyk, M.

AU - Adamska, E.

AU - Álvarez-Rodríguez, R.

AU - Andreyev, A. N.

AU - Barzakh, A. E.

AU - Benzoni, G.

AU - Berry, T.

AU - Borge, M. J.G.

AU - Carmona, M.

AU - Chrysalidis, K.

AU - Costache, C.

AU - Cubiss, J. G.

AU - Day Goodacre, T.

AU - De Witte, H.

AU - Eronen, T.

AU - Fedorov, D. V.

AU - Fedosseev, V. N.

AU - Fernández-Martínez, G.

AU - Fijałkowska, A.

AU - Fila, M.

AU - Fynbo, H.

AU - Galaviz, D.

AU - Galve, P.

AU - García-Díez, M.

AU - Ge, Z.

AU - Greenlees, P. T.

AU - Grzywacz, R.

AU - Henrich, C.

AU - Huyse, M.

AU - Ibáñez, P.

AU - Illana, A.

AU - Janas, Z.

AU - Jolie, J.

AU - Judson, D. S.

AU - Kankainen, A.

AU - Karayonchev, V.

AU - Kicińska-Habior, M.

AU - Konki, J.

AU - Kurcewicz, J.

AU - Lazarus, I.

AU - Licǎ, R.

AU - López-Montes, A.

AU - Raison, C.

AU - Simpson, G. S.

AU - Wadsworth, R.

N1 - Publisher Copyright: © 2024 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Open access publication funded by CERN.

PY - 2024/7/26

Y1 - 2024/7/26

N2 - The excited structure of the single-hole nucleus Sn131 populated by the β- decay of In131 was investigated in detail at the ISOLDE facility at CERN. This new experiment took advantage of isomeric purification capabilities provided by resonant ionization, making it possible to independently study the decay of each isomer for the first time. The position of the first-excited νh11/2 neutron-hole state was confirmed via an independent mass spectroscopy experiment performed at the Ion Guide Isotope Separator On-Line facility at the University of Jyväskylä. The level scheme of Sn131 was notably expanded with the addition of 31 new γ-ray transitions and 22 new excited levels. The γ-emitting excited levels above the neutron separation energy in Sn131 were investigated, revealing a large number of states, which in some cases decay by transitions to other neutron-unbound states. Our analysis showed the dependence between the population of these states in Sn131 and the β-decaying In131 state feeding them. Profiting from the isomer selectivity, it was possible to estimate the direct β feeding to the 3/2+ ground and 11/2- isomeric states, disentangling the contributions from the three indium parent states. This made possible to resolve the discrepancies in logft for first-forbidden transitions observed in previous studies, and to determine the β-delayed neutron decay probability (Pn) values of each indium isomers independently. The first measurement of subnanosecond lifetimes in Sn131 was performed in this work. A short T1/2=18(4)-ps value was measured for the 1/2+ neutron single-hole 332-keV state, which indicates an enhanced l-forbidden M1 behavior for the ν3s1/2-1→ν3d3/2-1 transition. The measured half-lives of high-energy states populated in the β decay of the (21/2+) second isomeric state (In131m2) provided valuable information on transition rates, supporting the interpretation of these levels as core-excited states analogous to those observed in the doubly-magic Sn132.

AB - The excited structure of the single-hole nucleus Sn131 populated by the β- decay of In131 was investigated in detail at the ISOLDE facility at CERN. This new experiment took advantage of isomeric purification capabilities provided by resonant ionization, making it possible to independently study the decay of each isomer for the first time. The position of the first-excited νh11/2 neutron-hole state was confirmed via an independent mass spectroscopy experiment performed at the Ion Guide Isotope Separator On-Line facility at the University of Jyväskylä. The level scheme of Sn131 was notably expanded with the addition of 31 new γ-ray transitions and 22 new excited levels. The γ-emitting excited levels above the neutron separation energy in Sn131 were investigated, revealing a large number of states, which in some cases decay by transitions to other neutron-unbound states. Our analysis showed the dependence between the population of these states in Sn131 and the β-decaying In131 state feeding them. Profiting from the isomer selectivity, it was possible to estimate the direct β feeding to the 3/2+ ground and 11/2- isomeric states, disentangling the contributions from the three indium parent states. This made possible to resolve the discrepancies in logft for first-forbidden transitions observed in previous studies, and to determine the β-delayed neutron decay probability (Pn) values of each indium isomers independently. The first measurement of subnanosecond lifetimes in Sn131 was performed in this work. A short T1/2=18(4)-ps value was measured for the 1/2+ neutron single-hole 332-keV state, which indicates an enhanced l-forbidden M1 behavior for the ν3s1/2-1→ν3d3/2-1 transition. The measured half-lives of high-energy states populated in the β decay of the (21/2+) second isomeric state (In131m2) provided valuable information on transition rates, supporting the interpretation of these levels as core-excited states analogous to those observed in the doubly-magic Sn132.

UR - http://www.scopus.com/inward/record.url?scp=85200118465&partnerID=8YFLogxK

U2 - 10.1103/PhysRevC.110.014328

DO - 10.1103/PhysRevC.110.014328

M3 - Article

SN - 2469-9985

VL - 110

JO - Phys. Rev. C

JF - Phys. Rev. C

IS - 1

M1 - 014328

ER -