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Una poderosa fuente de radio irrumpiendo hacia el Centro Galáctico
Scott D Hyman1, T Joseph W Lazio, Namir E Kassim
1Department of Physics and Engineering, Sweet Briar College, Sweet Briar, Virginia 24595, USA. shyman@sbc.edu
Nature
|March 4, 2005
Resumen
Los astrónomos han descubierto una nueva fuente de radio transitoria, GCRT J1745-3009, cerca del Centro Galáctico. Sus características únicas de estallido sugieren una clase previamente desconocida de transitorios cósmicos, ofreciendo información sobre eventos celestes dinámicos.
Área de la Ciencia:
- La radioastronomía es la radioastronomía.
- La astrofísica es la astrofísica.
- Los fenómenos astronómicos transitorios son fenómenos astronómicos que ocurren en el tiempo.
Sus antecedentes:
- Las fuentes astronómicas transitorias a menudo significan eventos explosivos y suelen ser alimentadas por objetos compactos.
- La radioastronomía ofrece observaciones de alta resolución temporal, pero está limitada por campos de visión estrechos, lo que lleva a una mala toma de muestras del cielo dinámico de radio.
- Los instrumentos de amplio campo en las bandas de rayos X y rayos gamma detectan rutinariamente fuentes transitorias, a diferencia de las capacidades actuales de radioastronomía.
Objetivo del estudio:
- Para reportar la detección de una nueva fuente de radio transitoria, GCRT J1745-3009.
- Para caracterizar las propiedades de ráfaga de esta nueva fuente y compararlas con los transitorios de radio conocidos.
- Explorar las implicaciones de su alta temperatura de brillo y densidad de energía para los mecanismos de emisión.
Principales métodos:
- Utilizó un programa de monitoreo de campo moderadamente amplio de la región del Centro Galáctico.
- Observaciones realizadas a una frecuencia de 0,33 GHz.
- Analizó las características temporales y las propiedades espectrales de las ráfagas detectadas.
Principales resultados:
- Se ha detectado una fuente de radio transitoria, GCRT J1745-3009, en la región del Centro Galáctico.
- Características de ráfaga observadas que son distintas de todas las clases conocidas de transitorios de radio.
- Se midió una temperatura de brillo de aproximadamente 10^16 K, lo que indica una densidad de energía extremadamente alta consistente con la emisión coherente.
Conclusiones:
- GCRT J1745-3009 representa una clase previamente desconocida de fuente de radio transitoria.
- Este descubrimiento pone de relieve el potencial de los nuevos radiotelescopios de amplio campo para descubrir nuevos fenómenos astronómicos.
- Los hallazgos sugieren que el cielo de radio dinámico puede albergar muchas más clases transitorias no descubiertas.
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