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Equipartition calculations

If the usual equipartition assumptions are made, then it is possible to estimate the magnetic field strength and pressure in the lobes. Assuming that the observed spectral index is maintained from 10 MHz to 100 GHz, that there are equal energies in the radiating electrons and other particles, and that the filling factor is unity, the derived magnetic field is Bmin ~ 5 × 10-6 h502/7 Gauss and pmin ~ 3.5 × 103 h504/7 cm-3 K for the hot spots. At the midpoint of the lobes these values are Bmin ~ 8 × 10-7 h502/7 Gauss and pmin ~ 2.3 × 102 h504/7 cm-3 K. At this redshift, the 3 K microwave background has an equivalent magnetic field of 4.2× 10-6 Gauss so the energy loss in the lobes should be dominated by inverse Compton scattering of this background, and the time for the electrons radiating at 1400 MHz to lose half of their energy will be ~ 108 h50-3/7 years.

Fri Feb 4 16:02:06 EST 2000