The radio continuum observations of the USS objects were carried out
with the VLA
as part of our multi-frequency study of the 34 4C ultra steep
spectrum sample (Chambers
et al. 1987, 1996a). With the identification of these high redshift
objects however, we
re-observed them to obtain the deeper images presented here.
Images with 1.2" resolution
at 20 cm (1465 MHz), 6 cm (4885 MHz), and 2 cm (14965 MHz) were
obtained in matched
VLA arrays (A,B, &C) so observations at different frequencies had
similar UV coverage
and could be directly compared with each other. High spatial
resolution (0.4" and 0.12")
observations were also obtained for several sources in A array at 6 cm
and 2 cm and in 2 cm
in B array. Phase calibration was done with nearby phase calibrators,
and the instrumental
polarization was determined from repeated observations of one
phase calibrator over a
range of hour angles. The fringe amplitudes were calibrated relative
to the standard VLA
flux calibrators 3C48 and 3C286. The data was reduced using the NRAO
AIPS software
package. Self-calibration was applied to improve the dynamic range
of the maps using 2
iterations of self-calibration for phase corrections and one
iteration for both phase and amplitude corrections.