A. Georgakakis, F. Carrera, et al.
The Athena mission concept will provide the technological leap required for a breakthrough in our understanding of AGN and galaxy evolution at the heyday of the Universe.
Its high throughput will allow the systematic study of AGN feedback to z~4 via the identification and measurement of blue-shifted X-ray absorption lines.
The excellent survey and spectral capabilities of Athena/WFI will complete the census of black hole growth by yielding samples of up to 100 times larger than is currently possible of the most heavily obscured, including Compton thick, AGN to redshifts z~4.
The demographics of this population relative to their hosts is fundamental for understanding how major black hole growth events relate to the build-up of galaxies.