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Aceleración de electrones en el corazón de los cinturones de radiación de Van Allen
G D Reeves1, H E Spence, M G Henderson
1Space Science and Applications Group, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. reeves@lanl.gov
Science (New York, N.Y.)
|July 27, 2013
Resumen
Los científicos han descubierto cómo los electrones ultrarelativistas obtienen altas energías en los cinturones de radiación de Van Allen de la Tierra. Las mediciones muestran que la aceleración local dentro de los cinturones, no de fuentes externas, es el mecanismo principal.
Área de la Ciencia:
- * Física del espacio y física del plasma.
- * Dinámica de la magnetosfera de la Tierra
- * Mecanismos de aceleración de partículas
Sus antecedentes:
- * Los cinturones de radiación de Van Allen albergan electrones ultrarelativistas, lo que plantea un enigma científico persistente.
- * Existen dos hipótesis principales: la aceleración radial de fuentes externas o la aceleración local dentro de los cinturones.
- * La comprensión de la aceleración de electrones es crucial para la predicción del clima espacial y la seguridad de los satélites.
Objetivo del estudio:
- * Para diferenciar entre los mecanismos de aceleración radial y local para los electrones del cinturón de Van Allen.
- * Proporcionar evidencia definitiva para el proceso de aceleración de electrones dominantes.
Principales métodos:
- * Se utilizaron datos de las sondas de tormenta del cinturón de radiación Van Allen (RBSP) de la NASA.
- * Perfiles radiales analizados de la densidad espacial de fase de los electrones.
- * Se compararon datos de observación con modelos teóricos de aceleración.
Principales resultados:
- * Los perfiles de densidad de espacio de fase observados apoyan fuertemente la aceleración local.
- * Los datos son inconsistentes con un proceso de aceleración predominantemente radial.
- * Se distingue directamente entre los dos mecanismos de aceleración propuestos.
Conclusiones:
- * La aceleración local dentro de los cinturones de radiación de Van Allen es el mecanismo principal para energizar los electrones.
- * El transporte radial de fuentes externas juega un papel menor en la aceleración de electrones de alta energía.
- * Estos hallazgos resuelven una pregunta de larga data en la física de la magnetosfera.
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