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Resonancias láser de alta resolución de helio antiprotónico en el superfluido He
Anna Sótér1,2, Hossein Aghai-Khozani1,3, Dániel Barna4,5
1Max-Planck-Institut für Quantenoptik, Garching, Germany.
Nature
|March 17, 2022
Resumen
Los átomos de helio antiprotónicos en el helio superfluido exhiben líneas espectrales nítidas, lo que permite la espectroscopia láser de alta resolución. Este avance permite el estudio detallado de los átomos exóticos y la detección potencial de la antimateria cósmica.
Área de la Ciencia:
- Física atómica y molecular
- Física de la antimateria
- Física de bajas temperaturas
Sus antecedentes:
- Las líneas espectrales ópticas de los átomos en líquidos se amplían significativamente, lo que dificulta la espectroscopia de alta resolución.
- El helio superfluido ofrece un ambiente transparente, frío e inerte, pero la ampliación espectral persiste para los átomos incrustados.
Objetivo del estudio:
- Para investigar el ancho de línea espectral de helio antiprotónico incrustado en helio superfluido.
- Para explorar el potencial de la espectroscopia láser de alta resolución de los átomos exóticos en el helio superfluido.
Principales métodos:
- Incorporar átomos de helio antiprotónicos en el helio superfluido.
- Observando la resonancia láser y midiendo el ancho de línea espectral.
- Analizando la estructura hiperfina debido a la interacción espín-espín electrón-antiprotón.
Principales resultados:
- El helio antiprotónico en el helio superfluido muestra un ancho de línea sub-gigahertz en su línea espectral visible.
- Se observó una fuerte reducción en el ancho de línea en la transición a la fase superfluida.
- Estructura hiperfina de resolución con una resolución espectral relativa de 2 partes en 10^6.
Conclusiones:
- El helio superfluido permite la espectroscopia láser de alta resolución del helio antiprotónico.
- Esta técnica se puede aplicar para estudiar otros átomos antinucleares, mesones e hiperones.
- Las líneas espectrales afiladas pueden facilitar la detección de antiprotones y antideuteronos de rayos cósmicos.
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