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Un repetidor gamma suave de bajo campo magnético
1Institut de Ciéncies de l'Espai, Consejo Superior de Investigaciones Científicas, Institut d'Estudis Espacials de Catalunya, Facultat de Ciéncies, Campus UAB, Torre C5-parell, 2a planta, 08193 Bellaterra (Barcelona), Spain. rea@ieec.uab.es
Science (New York, N.Y.)
|October 16, 2010
Resumen
Los magnetares, o estrellas de neutrones impulsadas por campos magnéticos intensos, pueden no requerir campos superficiales extremadamente altos. Este estudio encontró un repetidor gamma suave con ráfagas de tipo magnetar pero un campo magnético bajo, desafiando las teorías existentes.
Área de la Ciencia:
- La astrofísica es la astrofísica.
- Astrofísica de altas energías de alta energía.
- Física de las estrellas de neutrones Física de las estrellas de neutrones
Sus antecedentes:
- Los repetidores gamma blandos (SGR) y los púlsares de rayos X anómalos son fuentes de rayos X con ráfagas esporádicas.
- Se supone que estas fuentes son magnetares, alimentados por campos magnéticos extremos (10^1410^15 gauss).
Objetivo del estudio:
- Para investigar la intensidad del campo magnético de un repetidor gamma suave que exhibe una actividad similar a la de un magnetar.
- Para determinar si los campos magnéticos extremadamente altos son esenciales para el comportamiento de magnetar.
Principales métodos:
- Observaciones de rayos X del repetidor gamma suave SGR 0418+5729.
- Análisis de las emisiones de ráfagas para inferir las propiedades del campo magnético.
Principales resultados:
- SGR 0418+5729 exhibe explosiones similares a las de un magnetar.
- Las observaciones de rayos X indican un campo magnético dipolar por debajo de 7,5 × 10^12 gauss, típico de los pulsares de radio.
- Esto sugiere que la actividad similar al magnetar puede ocurrir con campos magnéticos más bajos de lo que se suponía anteriormente.
Conclusiones:
- Un campo magnético dipolar de alta superficie no es un requisito previo para la actividad de tipo magnetar.
- La población magnetar puede abarcar un espectro más amplio de intensidades de campo magnético, edades y estados evolutivos.
- Este hallazgo amplía nuestra comprensión de la diversidad de estrellas de neutrones y la formación de magnetares.
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