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Un entorno altamente magnetizado en un sistema binario de púlsares
Dongzi Li1, Anna Bilous2, Scott Ransom3
1Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA. dongzili@caltech.edu.
Nature
|May 17, 2023
Resumen
Los púlsares araña, como PSR B1744-24A, exhiben entornos muy magnetizados. La evidencia sugiere que estos campos magnéticos influyen en la emisión de púlsares y pueden ser similares a las condiciones encontradas en algunas ráfagas de radio rápidas (FRB).
Área de la Ciencia:
- Astronomía y astrofísica
- Física de los púlsares
- Sistemas de estrellas binarias
Sus antecedentes:
- Los púlsares araña son púlsares de milisegundos en órbitas cercanas con estrellas compañeras de baja masa.
- Estos sistemas exhiben fenómenos como la ablación de plasma, retrasos en el tiempo y eclipses de emisión de radio pulsar.
- Se supone que el campo magnético de la estrella compañera influye en la evolución del sistema binario y las propiedades del eclipse.
Objetivo del estudio:
- Para investigar el entorno magnetizado del sistema de púlsares araña PSR B1744-24A.
- Para analizar las variaciones de polarización y rotación para comprender las propiedades del campo magnético.
- Para explorar las conexiones potenciales entre el comportamiento de los púlsares de araña y las ráfagas rápidas de radio (FRB).
Principales métodos:
- Observación de los cambios de polarización circular (V) en el PSR B1744-24A.
- Análisis de cambios irregulares y rápidos en la medida de rotación (RM) en varias fases orbitales.
- Comparación del comportamiento de polarización observado con las características conocidas de FRB.
Principales resultados:
- Los cambios de perfil de polarización circular semirregular indican la conversión de Faraday, restringiendo el campo magnético acompañante a > 10 G.
- Las variaciones irregulares y rápidas de RM sugieren una fuerza de campo magnético del viento estelar > 10 mG.
- El comportamiento de polarización observado muestra similitudes con la repetición de ráfagas de radio rápidas (FRB).
Conclusiones:
- PSR B1744-24A posee un entorno altamente magnetizado, con campos magnéticos significativos tanto del compañero como de su viento estelar.
- Los fenómenos observados, incluida la conversión de Faraday y las variaciones de RM, proporcionan una fuerte evidencia de estos campos magnéticos.
- Las similitudes con los FRB sugieren que una fracción de los FRB puede originarse en sistemas binarios como los púlsares araña.
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