Physical Mechanisms That Shape the Morphologies of Extragalactic Jets

نویسنده

  • L. Zaninetti
چکیده

Se sugieren 5 métodos anaĺıticos para encontrar una ley que caracterice el decremento de la velocidad a lo largo del chorro. Los 2 primeros son modelos simples que examinan la variación de la velocidad en presencia de la resistencia de Newton o de Stoke. Se resuelve la ecuación que representa la conservación del momento a lo largo de un sector piramidal desde un punto de vista anaĺıtico (tercer modelo). La aplicación de la conservación del flujo del momento total nos permite deducir la velocidad de la galaxia como función del tiempo para velocidades clásicas (cuarto modelo) y para velocidades relativistas (quinto modelo). La variación de la velocidad a lo largo del chorro combinada con una adecuada composición de la velocidad de precesión del chorro, con la velocidad rotacional de la galaxia y con la dispersión de velocidades de la galaxia en el cúmulo nos permite trazar el patrón geométrico de las fuentes de radio con cabeza y cola. La aplicación de la teoŕıa/código desarrollado a las radiogalaxias NGC1265, NGC4061, NGC326, y Cygnus A nos da una dispersión de velocidades aproximada de la galaxia central en la dirección perpendicular al chorro. Introducimos una transición desde las galaxias cabeza-cola a las clásicas radiogalaxias dobles como función del incremento de la potencia mecánica del chorro.

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تاریخ انتشار 2006