Volume 613, May 2018
|Number of page(s)||31|
|Section||Cosmology (including clusters of galaxies)|
|Published online||23 May 2018|
Scale dependence of galaxy biasing investigated by weak gravitational lensing: An assessment using semi-analytic galaxies and simulated lensing data
Argelander-Institut für Astronomie, Universität Bonn,
Auf dem Hügel 71,
2 Faculty of Physics, Ludwig-Maximilians University, Scheinerstr. 1, 81679 München, Germany
3 Excellence Cluster Universe, Boltzmannstr. 2, 85748 Garching, Germany
Accepted: 12 December 2017
Galaxies are biased tracers of the matter density on cosmological scales. For future tests of galaxy models, we refine and assess a method to measure galaxy biasing as a function of physical scale k with weak gravitational lensing. This method enables us to reconstruct the galaxy bias factor b(k) as well as the galaxy-matter correlation r(k) on spatial scales between 0.01 h Mpc−1 ≲ k ≲ 10 h Mpc−1 for redshift-binned lens galaxies below redshift z ≲ 0.6. In the refinement, we account for an intrinsic alignment of source ellipticities, and we correct for the magnification bias of the lens galaxies, relevant for the galaxy-galaxy lensing signal, to improve the accuracy of the reconstructed r(k). For simulated data, the reconstructions achieve an accuracy of 3–7% (68% confidence level) over the above k-range for a survey area and a typical depth of contemporary ground-based surveys. Realistically the accuracy is, however, probably reduced to about 10–15%, mainly by systematic uncertainties in the assumed intrinsic source alignment, the fiducial cosmology, and the redshift distributions of lens and source galaxies (in that order). Furthermore, our reconstruction technique employs physical templates for b(k) and r(k) that elucidate the impact of central galaxies and the halo-occupation statistics of satellite galaxies on the scale-dependence of galaxy bias, which we discuss in the paper. In a first demonstration, we apply this method to previous measurements in the Garching-Bonn Deep Survey and give a physical interpretation of the lens population.
Key words: gravitational lensing: weak / large-scale structure of Universe / cosmology: observations / galaxies: statistics
© ESO 2018
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.