We present a detailed radio study of the young supernova remnant ( SNR ) G292.0+1.8 and its associated pulsar PSR J1124–5916 , using the Australia Telescope Compact Array at observing wavelengths of 20 , 13 and 6 cm .
We find that the radio morphology of the source consists of three main components : a polarized flat-spectrum central core coincident with the pulsar J1124–5916 , a surrounding circular steep-spectrum plateau with sharp outer edges and , superimposed on the plateau , a series of radial filaments with spectra significantly flatter than their surroundings .
H i absorption argues for a lower limit on the distance to the system of 6 kpc .

The core clearly corresponds to radio emission from a pulsar wind nebula powered by PSR J1124–5916 , while we conclude that the plateau represents the surrounding SNR shell .
The plateau ’ s sharp outer rim delineates the SNR ’ s forward shock , while the thickness of the plateau region demonstrates that the forward and reverse shocks are well-separated .
Assuming a distance of 6 kpc and an age for the source of 2500 yr , we infer an expansion velocity for the SNR of \sim 1200 km s ^ { -1 } , an ambient density \sim 0.9 cm ^ { -3 } , an ejected mass \sim 5.9 M _ { \odot } and a supernova explosion energy \sim 1.1 \times 10 ^ { 51 } erg .
We interpret the flat-spectrum radial filaments superimposed on the steeper-spectrum plateau as Rayleigh-Taylor unstable regions between the forward and reverse shocks of the SNR .
The flat radio spectrum seen for these features results from efficient second-order Fermi acceleration in strongly amplified magnetic fields .
Overall , SNR G292.0+1.8 shows an unusual set of properties not seen in any other SNR .
This source may reflect a unique stage in evolution , only seen for systems at an age of \sim 2500 yr , and only for which there is both a bright SNR shell and an energetic associated pulsar .