The Einstein Telescope (ET), a wide-band, future 3G gravitational wave detector, is to have expected detection rates of $sim 10^5 – 10^6$ BBH detections and $sim 7 times 10^4$ BNS detections in one year. The coalescence of compact binaries with total mass 20 – 100 $M_{odot}$, as typical of BH-BH or BH-NS binaries, will be visible up to redshift $zapprox 20$ and higher, thus facilitating the understanding of the dark era of the Universe preceding the birth of the first stars. The ET will therefore be a crucial instrument for population studies. We analyzed the compact binaries originating in stars from (i) Pop I and Pop II, (ii) Pop III, and (iii) globular clusters, with single ET using the ET-D design sensitivity for the analysis. We estimate the constraints on the chirp mass, redshift and merger rate with redshift for these classes of compact object binaries. We conclude that ET as a single instrument is capable of detecting and distinguishing different compact binary populations separated in chirp mass – redshift space. The mass distributions characteristics of such different compact binary populations can also be estimated with single ET. Assuming that sufficient number of binaries will be detected from each of these populations, we also show that such populations are distinguishable in the combined bulk detection.
