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Las ráfagas de radio transitorias de las estrellas de neutrones rotativas
M A McLaughlin1, A G Lyne, D R Lorimer
1Jodrell Bank Observatory, University of Manchester, Macclesfield, Cheshire SK11 9DL, UK. Maura.McLaughlin@manchester.ac.uk
Nature
|February 17, 2006
Resumen
Los astrónomos descubrieron once nuevas fuentes de radio que emiten ráfagas breves y dispersas. Estas señales de radio rápidas sugieren una nueva población de estrellas de neutrones giratorias en nuestra galaxia.
Área de la Ciencia:
- La astronomía y la astrofísica.
- La radioastronomía es una radioastronomía.
- Física de las estrellas de neutrones Física de las estrellas de neutrones
Sus antecedentes:
- El cielo de la radio sigue siendo en gran parte inexplorado para las señales transitorias, a pesar del alto potencial.
- Descubrimientos recientes ponen de relieve fuentes de radio variables previamente desconocidas en escalas de tiempo de minuto a hora.
Objetivo del estudio:
- Buscar y caracterizar fuentes de radio que exhiban un comportamiento transitorio en escalas de tiempo mucho más cortas (millisegundos).
- Para investigar la naturaleza y la población de estas fuentes de radio efímeras recién descubiertas.
Principales métodos:
- Se llevó a cabo una búsqueda de transitorios rápidos de radio.
- Se analizaron los tiempos de llegada de la ráfaga para identificar periodicidades.
- Cambios medidos en el período de pulso e intensidad inferida del campo magnético para fuentes seleccionadas.
Principales resultados:
- Se detectaron once objetos con ráfagas aisladas y dispersas que duraron de 2 a 30 ms.
- Periodicidades identificadas (0,4-7 s) en diez fuentes, indicativas de estrellas de neutrones giratorias.
- Inferido una alta intensidad de campo magnético (5 x 10 ^ 13 G) para una fuente.
Conclusiones:
- Las fuentes descubiertas representan una nueva población de estrellas de neutrones efímeras y potencialmente rotativas.
- Esta población puede estar relacionada con otras clases de estrellas de neutrones aisladas observadas en todo el espectro electromagnético.
- La población galáctica total de estas fuentes probablemente excede a la de los pulsares de radio conocidos.
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