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Cambios rápidos de giro alrededor de una ráfaga de radio rápida de magnetar
Chin-Ping Hu1,2, Takuto Narita3, Teruaki Enoto4,5
1Department of Physics, National Changhua University of Education, Changhua City, Taiwan. cphu0821@gm.ncue.edu.tw.
Nature
|February 15, 2024
Resumen
Dos fallas magnetares, observadas en SGR 1935+2154, coincidieron con una ráfaga de radio rápida (FRB). Estas fallas alteraron rápidamente la estrella de neutrones.
Área de la Ciencia:
- * Astrofísica
- * Astrofísica de altas energías
- * Física de las estrellas de neutrones
Sus antecedentes:
- * Los magnetares son estrellas de neutrones con campos magnéticos muy fuertes (1014 Gauss).
- * Exhiben fenómenos de rayos X como explosiones y mejoras de flujo.
- * El origen de las ráfagas rápidas de radio (FRB) de los magnetares no se entiende completamente.
Objetivo del estudio:
- * Para investigar el comportamiento de rayos X del magnetar SGR 1935+2154 alrededor de un evento FRB.
- * Comprender el mecanismo de fallo magnetar y su conexión con la generación de FRB.
Principales métodos:
- * Observaciones de rayos X del magnetar SGR 1935+2154.
- * Análisis de los cambios en la frecuencia de giro y la emisión de rayos X durante los eventos de fallas.
Principales resultados:
- * Se observaron dos fallas magnéticas significativas dentro de las nueve horas, entre paréntesis un FRB.
- * Cada fallo causó un aumento sustancial en la frecuencia de giro, entre los más grandes registrados para las estrellas de neutrones.
- * Se produjo una rápida fase de desconexión entre fallas, con un aumento y luego una disminución de la emisión de rayos X y la tasa de ráfaga.
Conclusiones:
- * Las fallas sugieren un acoplamiento entre la corteza del magnetar y la magnetosfera.
- * Un efímero viento magnetosférico probablemente causó el rápido giro hacia abajo.
- * Este viento puede alterar las condiciones de la magnetosfera, lo que podría desencadenar eventos de FRB.
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