Hi Kamal,
I apologize for the delay. Aperture jitter is not something that is characterized on this part. The datasheet only specifies a typical value of 10ps (RMS) based on simulation. If two ADCs are being used for simultaneous sampling then the RMS jitter between their measurements would just be ((10ps)^2 + (10ps)^2)^(1/2) ~= 14ps or +/-42ps worst case assuming a factor of 3 for a Gaussian distribution. Of course this is assuming the clock signals driving the sampling switches of the two ADCs are in-phase and precise (jitter << 10ps) so that their contribution is negligible.
Best Regards,
Harsha Munikoti