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Halos de color gigantes inducidos por radiación en cuarzo: solución a un acertijo
Science (New York, N.Y.)
|October 6, 1989
Resumen
Los halos de color inducidos por radiación (RICH) en los minerales suelen coincidir con los rangos de partículas alfa. Los RICH anómalos en cuarzo sugieren la migración de agujeros, ofreciendo información sobre la difusión de carga.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Ciencia de los materiales Ciencia de los materiales.
- Física de las radiaciones Física de la radiación
Sus antecedentes:
- Los halos de color inducidos por radiación (RICH) alrededor de las inclusiones radiactivas en la mica generalmente se correlacionan con los rangos de partículas alfa.
- Las desviaciones de esta correlación han dado lugar a interpretaciones complejas.
Objetivo del estudio:
- Para investigar los RICH anómalos en cuarzo.
- Para identificar la naturaleza de los centros de color en estos RICHs anómalos.
- Proponer un mecanismo para las discrepancias observadas.
Principales métodos:
- Análisis de RICH en muestras de cuarzo.
- Identificación de los centros de color utilizando métodos espectroscópicos (implicados).
- Comparación de los radios observados con los rangos calculados de partículas alfa.
Principales resultados:
- Se identificaron tres RICH en cuarzo como centros de trampa de agujero de aluminio.
- Los radios internos coincidían con el rango predicho de partículas alfa energéticas (39 micrómetros).
- Los centros de color observados se extendían significativamente más allá de este rango, hasta 100 micrómetros.
Conclusiones:
- Los RICH anómalos en cuarzo se atribuyen a los centros de atrapamiento de agujeros de aluminio.
- Los radios extendidos sugieren la migración del agujero de banda de valencia a lo largo de potenciales de carga inducidos por la radiación.
- Estos RICH sirven como modelos naturales para el estudio de la difusión de carga ultra lenta.
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