A Detailed Study of the Lobes of Eleven Powerful Radio Galaxies
  Radio lobes of a sample of eleven very powerful classical double radio
galaxies were studied. Each source was rotated so that the symmetry axis of the
source was horizontal, and vertical cross-sectional cuts were taken across the
source at intervals of one beam size. These were used to study the
cross-sectional surface brightness profiles, the width of each slice, radio
emissivity as a function of position across each slice, the first and second
moments, and the average surface brightness, minimum energy magnetic field
strength, and pressure of each slice. A Gaussian provides a good description of
the surface brightness profile of cross-sectional slices. The Gaussian FWHM as
a function of distance from the hot spot first increases and then decreases
with distance from the hot spot. The width as a function of distance from the
hot spot is highly symmetric on each side of the source. The radio emissivity
is often close to flat across a slice, indicating a roughly constant emissivity
and pressure for that slice. Some slices show variations in radio emissivity
that indicate an ``edge-peaked'' pressure profile for that slice; these often
occur in slices near the local maxima of the bridge width. The emissivity does
not exhibit any signature of emission from a jet. The first moment is generally
quite close to zero indicating only small excursions of the ridge line from the
symmetry axis of the source. The second moment indicates the same source shape
as is found using the Gaussian FWHM. The average magnetic field strength and
pressure decrease with increasing distance from the hot spot, reaching a
roughly constant value at a location that is typically just before the location
of a local maximum of the bridge width. These results are interpreted in terms
of a heuristic model for the radio lobes.
