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El tamaño del protón
Randolf Pohl1, Aldo Antognini, François Nez
1Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany. randolf.pohl@mpq.mpg.de
Nature
|July 9, 2010
Resumen
Los investigadores midieron el protón.
Área de la Ciencia:
- Física atómica y molecular Física atómica y molecular
- La electrodinámica cuántica (QED, por sus siglas en inglés)
- Física de las partículas Física de las partículas
Sus antecedentes:
- Las propiedades del protón, como su radio de carga, no se comprenden completamente.
- Las mediciones existentes del radio de carga del protón tienen limitaciones en la precisión.
- Las mediciones precisas del radio del protón son cruciales para probar las teorías fundamentales de la física.
Objetivo del estudio:
- Para mejorar la precisión de la medición del radio de carga del protón.
- Para investigar las discrepancias entre diferentes métodos de medición.
- Para probar la validez de los cálculos de la electrodinámica cuántica (QED).
Principales métodos:
- Se utilizó la espectroscopia láser pulsada en hidrógeno muónico.
- Se midió el desplazamiento muónico de Lamb con alta precisión.
- Calculó el radio de carga del protón basado en el desplazamiento de Lamb medido y modelos teóricos.
Principales resultados:
- Determinado un nuevo valor para el radio de carga del protón: r (p) = 0,84184 (p) = 0,84184 (p) fm.
- Este valor difiere en 5.0 desviaciones estándar del valor actual de CODATA.
- Los hallazgos sugieren posibles problemas con los cálculos de QED o la constante de Rydberg.
Conclusiones:
- La nueva medición del radio de carga del protón desafía los valores existentes.
- Las discrepancias pueden requerir revisiones en los cálculos de QED o constantes fundamentales.
- Se necesita más investigación para resolver las diferencias observadas.
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