A radio-far infrared correlation is constructed for a sample of blueearly-type galaxies in which optical-line emissions are known to be originatingin star-forming activities without any significant contribution from activegalactic nuclei. A tight radio-far infrared correlation similar to that instar-forming late-type galaxies is seen in these blue early-type galaxies. Theaverage value of the 'q' parameter is estimated as $2.35\pm0.15$ with a scatterof 0.18 dex in the radio far-infrared correlation. The tight radio-far infraredcorrelation implies that the radio emission is primarily from the synchrotronprocess, which allowed us to estimate magnetic field strengths in early-typegalaxies assuming equipartition between cosmic rays and magnetic field energydensities. The average value of the magnetic field strengths in early-typegalaxies is estimated as $\sim10\mu$G, which is similar to magnetic fieldstrengths in spiral galaxies. The magnetic fields in early-type galaxies aremost likely captured during a tidal encounter with a gas-rich galaxy. Thesubsequent evolution in terms of amplification, regularization and sustainmentof fields over long periods may take place in some dynamical components such asrings.
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