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Updated: May 22, 2026

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Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
Observación de la resonancia magnética nuclear del 239Pu
H Yasuoka1, G Koutroulakis, H Chudo
1Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
Resumen
Los investigadores detectaron la esquiva señal de resonancia magnética nuclear del plutonio-239 (239Pu) en el dióxido de plutonio (PuO2). Este avance abre nuevas vías para el estudio del plutonio.
Área de la Ciencia:
- Física nuclear es la física nuclear.
- La espectroscopia es una técnica de espectroscopia.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- El núcleo de spin-1⁄2 de plutonio-239 ((239) Pu) es teóricamente activo en la espectroscopia de resonancia magnética nuclear (RMN).
- A pesar de las predicciones teóricas, la señal de RMN de (239) Pu ha permanecido sin ser detectada durante cinco décadas, lo que dificulta la caracterización nuclear.
Objetivo del estudio:
- Para lograr la primera detección de la señal de RMN de (239) Pu.
- Para caracterizar las propiedades nucleares de (239) Pu utilizando espectroscopia de RMN.
Principales métodos:
- Se utilizó la espectroscopia de resonancia magnética nuclear (RMN) en una muestra sólida de dióxido de plutonio (PuO2).
- Realizó experimentos bajo una amplia gama de campos magnéticos externos (3 a 8 teslas) a temperaturas criogénicas (4 Kelvin).
- Mapeó la dependencia del campo externo de la frecuencia de resonancia para identificar la señal (239) Pu.
Principales resultados:
- Se observó y registró con éxito la señal de resonancia de RMN (239) Pu en PuO2.
- Se determinó que la relación nuclear giromagnética de (239) Pu en PuO2 es de 2.856 ± 0.001 MHz/T.
- Se ha estimado la relación giromagnética nuclear desnuda (239) Pu (~2,29 MHz/T) y el momento magnético nuclear (~0,15 μN).
Conclusiones:
- La detección de la señal de RMN de (239) Pu supera un desafío experimental de 50 años.
- Este hallazgo valida las expectativas teóricas y proporciona datos cruciales para comprender las propiedades nucleares del plutonio.
- La metodología establecida y los parámetros determinados allanan el camino para futuros estudios de RMN en materiales que contienen plutonio.
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