A high Mach number, radiatively cooled jet of astrophysical interest has be
en produced using intense laser irradiation of a gold cone. The evolution o
f the jet was imaged in emission and in radiography, and the temperature wa
s measured with Thomson scattering. Comparison with numerical simulations s
hows that radiative cooling is a dominant mechanism in the collapse of the
Au plasma jet on axis, with temperatures plummeting and peak densities incr
easing, each by an order of magnitude in similar to 1/2 ns. In dimensionles
s terms, aspects of this jet are similar to radiative astrophysical jets.