2020/12/02 by P. Šimon, Patrick Simon, Stefan Hilbert · 4 citations
Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy and Astrophysical Research #Astrophysics #Correlation function (quantum field theory) #Dark matter #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Galaxy rotation curve #Physics #Redshift #Star formation #Stellar mass #Weak gravitational lensing #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.1051/0004-6361/202038119
published in Astronomy and Astrophysics 646, A71 (EDP Sciences) · 17+13(Appendix) pages, 13+6 figures; Figs. A.1-A.4 are key figures; accepted by A&A, in press; Monte-Carlo realisations of $b(k)$ and $r(k)$ will be provided as online material on http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/
openalex publication_date 2020/12/02 · openalex created_date 2020/12/07 · arxiv created 2020/12/22 · arxiv updated 2021/02/17 · openalex updated_date 2026/08/05
Galaxy models predict a tight relation between the clustering of galaxies and dark matter on cosmological scales, but predictions differ notably in the details. We used this opportunity and tested two semi-analytic models by the Munich and Durham groups with data from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). For the test we measured the scale-dependent galaxy bias factor b ( k ) and correlation factor r ( k ) from linear to non-linear scales of k ≈ 10 h Mpc −1 at two redshifts z̄ = 0.35, 0.51 for galaxies with stellar mass between 5 × 10 9 and 3 × 10 11 h 70 −2 M ⊙ . Our improved gravitational lensing technique accounts for the intrinsic alignment of sources and the magnification of lens galaxies for better constraints for the galaxy-matter correlation r ( k ). Galaxy bias in CFHTLenS increases with k and stellar mass; it is colour-dependent, revealing the individual footprints of galaxy types. Despite a reasonable model agreement for the relative change with both scale and galaxy properties, there is a clear conflict for b ( k ) with no model preference: the model galaxies are too weakly clustered. This may flag a model problem at z ≳ 0.3 for all stellar masses. As in the models, however, there is a high correlation r ( k ) between matter and galaxy density on all scales, and galaxy bias is typically consistent with a deterministic bias on linear scales. Only our blue and low-mass galaxies of about 7 × 10 9 h 70 −2 M ⊙ at z̄ = 0.51 show, contrary to the models, a weak tendency towards a stochastic bias on linear scales where r ls = 0.75 ± 0.14 (stat.) ± 0.06 (sys.). This result is of interest for cosmological probes, such as E G , that rely on a deterministic galaxy bias. We provide Monte Carlo realisations of posterior constraints for b ( k ) and r ( k ) in CFHTLenS for every galaxy sample in this paper at the CDS.