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تسجيل مستخدم جديدFar-infrared - radio correlation and magnetic field strength in star-forming early-type galaxies
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A tight far-infrared - radio correlation similar to that in star-forming late-type galaxies is also indicated in star-forming blue early-type galaxies, in which the nuclear optical-line emissions are primarily due to star-forming activities without a significant contribution from active galactic nuclei. The average value of far-infrared to 1.4 GHz radio flux-ratio commonly represented as the $q$ parameter is estimated to be $2.35pm0.05$ with a scatter of 0.16 dex. The average star formation rate estimated using 1.4 GHz radio continuum is $sim6$ M$_{odot}$ yr$^{-1}$ in good agreement with those estimated using far-infrared and H$alpha$ luminosities. The radio emission is detected mainly from central region which could be associated with the star-forming activities, most likely triggered by recent tidal interactions. The average thermal contribution to total radio flux is estimated to be $sim12$ per cent. The average value of the magnetic field strengths in the star-forming early-type galaxies is estimated to be 12$^{+11}_{-4}$ $mu$G. These magnetic fields are very likely generated via fast amplification in small-scale turbulent dynamos acting in the star-bursting regions.
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