Active galactic nuclei and their large-scale structure: an eROSITA mock catalogue. Issue 2 (20th May 2019)

• Record Type: Journal Article
• Authors: Comparat, J; Merloni, A; Salvato, M; Nandra, K; Boller, T; Georgakakis, A; Finoguenov, A; Dwelly, T; Buchner, J; Del Moro, A; Clerc, N; Wang, Y; Zhao, G; Prada, F; Yepes, G; Brusa, M; Krumpe, M; Liu, T
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 487:Issue 2(2019)
• Page Start: 2005
• Page End: 2029
• Publication Date: 2019-05-20
• Subjects: galaxies: active -- large-scale structure of Universe -- cosmology: observations; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stz1390
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: In the context of the upcoming SRG/eROSITA survey, we present an N -body simulation-based mock catalogue for X-ray-selected active galactic nucleus (AGN) samples. The model reproduces the observed hard X-ray AGN luminosity function (XLF) and the soft X-ray logN–logS from redshift 0 to 6. The XLF is reproduced to within$\pm 5{{\ \rm per\ cent}}$ and the logN-logS to within$\pm 20{{\ \rm per\ cent}}$ . We develop a joint X-ray – optical extinction and classification model. We adopt a set of empirical spectral energy distributions to predict observed magnitudes in the UV, optical, and NIR. With the latest eROSITA all sky survey sensitivity model, we create a high-fidelity full-sky mock catalogue of X-ray AGN. It predicts their distributions in right ascension, declination, redshift, and fluxes. Using empirical medium resolution optical spectral templates and an exposure time calculator, we find that 1.1 × 10 6 (4 × 10 5 ) fibre-hours are needed to follow-up spectroscopically from the ground the detected X-ray AGN with an optical magnitude 21 < r < 22.8 (22.8 < r < 25) with a 4-m (8-m) class multiobject spectroscopic facility. We find that future clustering studies will measure the AGN bias to the per cent level at redshift z < 1.2 and should discriminate possible scenarios of galaxy-AGN co-evolution. We predict the accuracy to which the baryon acoustic oscillation standard ruler will be measured using X-ray AGN: better than 3 per cent for AGN between redshift 0.5 to 3 and better than 1 per cent using the Ly α forest of X-ray QSOs discovered between redshift 2 and 3. eROSITA will provide an outstanding set of targets for future galaxy evolution and cosmological studies.