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Una población de púlsares de milisegundos de rayos gamma vistos con el Telescopio de Gran Área Fermi
A A Abdo1, M Ackermann, M Ajello
1Space Science Division, Naval Research Laboratory,Washington, DC 20375, USA.
Science (New York, N.Y.)
|July 4, 2009
Resumen
Los púlsares de milisegundos (MSP) en sistemas binarios pueden recuperar una "segunda vida", girando para emitir pulsaciones detectables de rayos gamma. Estos hallazgos sugieren un mecanismo de emisión común entre los MSP y los púlsares jóvenes.
Área de la Ciencia:
- * Astronomía y Astrofísica.
- * Astrofísica de altas energías.
- * Física de las estrellas de neutrones
Sus antecedentes:
- * Los púlsares son estrellas de neutrones de rápida rotación que emiten haces de radiación electromagnética.
- * Inicialmente, los púlsares giran hacia abajo debido al frenado electromagnético durante millones de años.
- * Las estrellas de neutrones en sistemas binarios pueden acumular materia, lo que lleva a una "segunda vida" como pulsares de milisegundos (MSP).
Objetivo del estudio:
- * Para buscar pulsaciones de rayos gamma de pulsares de milisegundos conocidos (MSP) fuera de los cúmulos globulares.
- * Para investigar las propiedades de emisión de púlsares reciclados.
- * Para comparar las características de los MSP con las de los púlsares jóvenes y energéticos.
Principales métodos:
- * Se utilizaron datos del Telescopio de Gran Área Fermi (LAT).
- * Se emplearon parámetros de rotación obtenidos a partir de observaciones con radiotelescopios.
- * Se analizaron datos de rayos gamma para detectar pulsaciones de una muestra de MSP.
Principales resultados:
- * Se detectaron pulsaciones significativas de rayos gamma en ocho MSP previamente conocidos.
- * Se observó que los perfiles de pulso de rayos gamma y las propiedades espectrales de estos MSP son similares a las de los jóvenes púlsares de rayos gamma.
- * Se identificaron similitudes en los mecanismos de emisión entre los MSP y los púlsares jóvenes.
Conclusiones:
- * Los púlsares de milisegundos exhiben propiedades consistentes con un mecanismo de emisión común compartido con los púlsares jóvenes.
- * La emisión tanto en MSPs como en púlsares jóvenes parece originarse en regiones distantes de la superficie de la estrella de neutrones.
- * Este estudio destaca la importancia de las interacciones binarias en la evolución y las propiedades observables de las estrellas de neutrones.
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