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Una doble hélice cósmica en el cuásar arquetípico 3C2733
1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany. alobanov@mpifr-bonn.mpg.de
Science (New York, N.Y.)
|October 6, 2001
Resumen
Se encontró evidencia directa de inestabilidad plasmática en chorros extragalácticos utilizando observaciones de radio. Una doble estructura helicoidal, indicativa de la inestabilidad de Kelvin-Helmholtz, fue observada en el quásar 3C273.
Área de la Ciencia:
- La astrofísica es la astrofísica.
- Física del plasma es la física del plasma.
Sus antecedentes:
- La comprensión de las salidas relativistas de los núcleos galácticos activos (AGN) es clave para la astrofísica.
- La evidencia directa de la inestabilidad del plasma en los chorros extragalácticos sigue siendo difícil de alcanzar.
Objetivo del estudio:
- Para encontrar evidencia directa de la inestabilidad del plasma en los chorros extragalácticos.
- Para entender la naturaleza de las salidas relativistas de AGN.
Principales métodos:
- Observaciones interferométricas de radio utilizando el radiotelescopio en órbita HALCA y telescopios terrestres.
- Imágenes de alta resolución del chorro del cuásar 3C273.
Principales resultados:
- La emisión resuelta a través del chorro reveló una estructura doble helicoidal.
- Esta estructura es consistente con la inestabilidad de Kelvin-Helmholtz.
- Identificó al menos cinco modos de inestabilidad, modelados por un chorro de luz (factor Lorentz 2, número de Mach 3.5).
Conclusiones:
- La doble hélice observada proporciona evidencia directa de la inestabilidad del plasma en los chorros extragalácticos.
- El modelo reproduce con precisión la estructura interna del jet y su morfología general.
- Este hallazgo avanza en nuestra comprensión de las salidas astrofísicas relativistas.
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