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Diferentes oscilaciones de ángulo de polarización de una fuente de ráfagas de radio rápidas repetitivas
R Luo1,2,3, B J Wang1,2, Y P Men1,2
1Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing, China.
Nature
|October 29, 2020
Resumen
Las observaciones de ráfagas rápidas de radio (FRB) revelan diversos cambios de ángulo de polarización. Estos hallazgos apoyan los orígenes magnetosféricos de la emisión de FRB, desafiando los modelos de radiación basados en choques.
Área de la Ciencia:
- La astrofísica
- La radioastronomía
Sus antecedentes:
- Las ráfagas rápidas de radio (FRB) son transitorios de radio de milisegundos de duración de origen desconocido.
- Las teorías actuales sugieren mecanismos de emisión que involucran magnetosferas de estrellas de neutrones o choques relativistas.
- Las observaciones de polarización son cruciales para comprender la emisión de FRB, pero han arrojado datos desconcertantes.
Objetivo del estudio:
- Investigar el mecanismo de emisión de ráfagas rápidas de radio (FRB) a través de observaciones detalladas de polarización.
- Para analizar las propiedades de polarización de múltiples ráfagas de una sola fuente FRB (FRB 180301).
Principales métodos:
- Se observaron 15 ráfagas de la fuente FRB 180301.
- Analizó las variaciones de ángulo de polarización dentro de estos estallidos.
Principales resultados:
- Se observaron varios cambios de ángulo de polarización en siete de los 15 estallidos analizados.
- La diversidad de las características de polarización se observó a través de las explosiones observadas.
Conclusiones:
- Las diversas oscilaciones de ángulo de polarización observadas en FRB 180301 son consistentes con un origen magnetosférico para la emisión de radio.
- Estos hallazgos son desfavorables para los modelos de radiación que invocan choques relativistas como el mecanismo de emisión primario para los FRB.
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