C. C. Onuchukwu,1,2 A. A. Ubachukwu2, and F. C. Odo2
1 Dept of Physics, Anambra State University, Uli, Anambra State, PMB 02, Nigeria. (onuchukwu71chika@yahoo.com).
2 Department of Physics And Astronomy, University of Nigeria Nsukka, Nigeria.
Received 2013 April 22.
Accepted 2013 December 17.
RESUMEN
Presentamos un modelo cinemático para las asimetrías en las radiofuentes, el cual nos permite estimar la velocidad proyectada (mancha caliente/avance del lóbulo) en fuentes de radio de alta luminosidad usando el cociente entre las longitudes delos brazos (Q) y el cociente delos flujos aparentes (R). Obtenemos una velocidad media proyectada a lo largo de la visual ‹β̅› = 0.15 ± 0.05 para todas las fuentes de nuestra muestra utilizando el parámetro Q, y ‹β̅› ~ 0.12– 0.32 para ρ = 2α + 1(donde ρ es el índice del espectro de la energía de los electrones) usando el parámetro R. Nuestros resultados indican que el modelo adoptado para la evolución del brillo del elemento de plasma afecta los valores de la velocidad proyectada. Mediante análisis de regresión se encuentra que las velocidades estimadas usando los parámetros Q y R tienen cierta correlación con la distancia (L) y con la luminosidad (P), especialemente en el caso de los cuasares.
ABSTRACT
We present a kinematic model for asymmetries in radio sources, which enabled an estimation of the projected hotspot/lobe advance speed for high-luminosity radio sources using the arm-length ratio (Q) and apparent flux ratio (R). We obtain a mean projected speed along the line of sight ‹β̅› = 0.15 ± 0.05 for all the sources in our sample, using the Q parameter and ‹β̅› ~ 0.12– 0.32 for ρ = 2α + 1 (where ρ is the electron energy spectrum index) using the R parameter. Our results indicate that the adopted model of brightness evolution of plasma element affects the values of projected speed. Regression analyses indicate that the estimated speeds using the Q and R parameters show some correlation with distance (L) and luminosity (P), especiallyfor quasars.
Key Words: galaxies: active – galaxies: general – galaxies: kinematics and dynamics – methods: data analysis.
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