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Pulsaciones ópticas del anómalo púlsar de rayos X 4U0142+61
1Division of Physics, Mathematics, and Astronomy, California Institute of Technology, MS 405-47, Pasadena, California 91125, USA. bdk@srl.caltech.edu
Nature
|May 31, 2002
Resumen
Los púlsares anómalos de rayos X (AXP) son estrellas de neutrones altamente magnetizadas llamadas magnetares. Las pulsaciones ópticas detectadas de AXP 4U0142+61 confirman su naturaleza magnetar, vinculando AXPs y repetidores blandos de rayos gamma.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Astrofísica de altas energías de alta energía.
- Física de las estrellas de neutrones Física de las estrellas de neutrones
Sus antecedentes:
- Los púlsares anómalos de rayos X (AXP) exhiben luminosidades de rayos X que exceden con mucho su pérdida de energía de rotación, lo que sugiere una fuente de energía alternativa.
- Los magnetares, estrellas de neutrones con campos magnéticos superficiales >10 ^ 14 G, son una hipótesis líder para los AXP, alineándolos con repetidores blandos de rayos gamma (SGR).
- Las observaciones anteriores de la contraparte óptica de AXP 4U0142+61 fueron consistentes con magnetares, pero también con otros objetos como enanas blancas magnetizadas o estrellas de neutrones en acrecentamiento.
Objetivo del estudio:
- Para investigar la naturaleza del Pulsar Anomalo de Rayos X 4U0142+61 mediante la búsqueda de pulsaciones ópticas.
- Diferenciar entre los modelos de magnetares y las explicaciones alternativas para la emisión de AXP 4U0142+61.
- Establecer un vínculo directo de observación entre los AXP y los repetidores blandos de rayos gamma.
Principales métodos:
- Detección de pulsaciones ópticas del binario de rayos X 4U0142+61.
- Medición de la fracción pulsada de la luz óptica.
- Comparación de la fracción pulsada óptica con la fracción pulsada de rayos X.
Principales resultados:
- Se detectaron pulsaciones ópticas desde el AXP 4U0142+61.
- La fracción pulsada de la luz óptica se midió en un 27%.
- La fracción pulsada óptica es de 5 a 10 veces mayor que la fracción pulsada suave de rayos X.
Conclusiones:
- La detección de pulsaciones ópticas significativas confirma que 4U0142+61 es un magnetar.
- Este hallazgo establece una relación observacional directa entre los pulsares de rayos X anómalos y los repetidores de rayos gamma blandos.
- Las vías evolutivas precisas que conectan AXPs, SGR y púlsares de radio ordinarios siguen siendo una pregunta abierta.
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