We present 8.4 GHz VLA A-array and 1.4 GHz VLBA results on the radio continuum emission from the highest redshift radio-loud quasar known to date , the z = 6.12 QSO J1427+3312 .
The VLA observations show an unresolved steep spectrum source with a flux density of 250 \pm 20 { \mu } Jy at 8.4 GHz and a spectral index value of \alpha ^ { 8.4 } _ { 1.4 } = -1.1 .
The 1.4 GHz VLBA images reveal several continuum components with a total flux density of 1.778 \pm 0.109 mJy , which is consistent with the flux density measured with the VLA at 1.4 GHz .
Each of these components is resolved with sizes of a few milliarcseconds , and intrinsic brightness temperatures on the order of 10 ^ { 7 } to 10 ^ { 8 } K. The physical characteristics as revealed in these observations suggest that this QSO may be a Compact Symmetric Object , with the two dominant components seen with the VLBA , which are separated by 31 mas ( 174 pc ) and have intrinsic sizes of \sim 22 - 34 pc , being the two radio lobes that are confined by the dense ISM .
If indeed a CSO , then the estimated kinematic age of this radio AGN is only 10 ^ { 3 } yr .