Structure of 128Sn selectively populated in the β decay of the 128In ground state

High-resolution γ -ray spectroscopy and fast-timing methods were employed to study the excited structure of 128Sn, populated via the β-decay chain of 128Cd → 128In → 128Sn. The experiment was performed by online mass separation at the ISOLDE facility at CERN, profiting from intense and pure Cd beams...

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Detalles Bibliográficos
Autores: Llanos Expósito, Marcos, Benito García, Jaime, Fraile Prieto, Luis Mario, Illana Sisón, Andrés, Briz Monago, José Antonio, Encina Baranda, Nerea, López Herraiz, Joaquín, Rodríguez Murias, Javier, Martínez Nouvilas, Víctor, Sánchez Tembleque Verbo, Víctor, Udías Moinelo, José Manuel
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/122578
Acceso en línea:https://hdl.handle.net/20.500.14352/122578
Access Level:acceso abierto
Palabra clave:539.1
Picosecond lifetime measurements
Neutron-rich nuclei
Transition-probabilities
Beta decay
Electromagnetic transitions
Nuclear structure & decays
90 ≤ A ≤ 149
Lifetimes & widths
Radioactive beams
Shell model
Física nuclear
2207 Física Atómica y Nuclear
Descripción
Sumario:High-resolution γ -ray spectroscopy and fast-timing methods were employed to study the excited structure of 128Sn, populated via the β-decay chain of 128Cd → 128In → 128Sn. The experiment was performed by online mass separation at the ISOLDE facility at CERN, profiting from intense and pure Cd beams obtained by a temperature-controlled quartz transfer line combined with resonant laser ionization. An extended 128Sn level scheme populated in the β− decay of the low-spin 128In isomer was constructed, adding a total of 81 new γ -ray transitions and 30 new levels. Lifetimes of excited states were measured using time-delayed βγ (t) and γ γ (t) coincidences. The lifetime of the (4+) state was measured for the first time, making it possible to deduce the B(E2; 4+ → 2+) transition strength. The previously measured (5−) state was reassessed with improved statistics. Additionally, an upper limit for the lifetime of the state at 2378 keV was established. The derived reduced transition probabilities support a tentative spin-parity assignment of (4−) for this level. The experimental level scheme and transition probabilities are compared with available shell-model calculations.