English

KiDS+VIKING-450: An internal-consistency test for cosmic shear tomography with a colour-based split of source galaxies

Cosmology and Nongalactic Astrophysics 2021-02-24 v2

Abstract

We performed an internal-consistency test of the KiDS+VIKING-450 (KV450) cosmic shear analysis with a colour-based split of source galaxies. Utilising the same measurements and calibrations for both sub-samples, we inspected the characteristics of the shear measurements and the performance of the calibration pipelines. On the modelling side, we examined the observational nuisance parameters, specifically those for the redshift calibration and intrinsic alignments, using a Bayesian analysis with dedicated test parameters. We verified that the current nuisance parameters are sufficient for the KV450 data to capture residual systematics, with slight deviations seen in the second and the third redshift tomographic bins. Our test also showcases the degeneracy between the inferred amplitude of intrinsic alignments and the redshift uncertainties in low redshift tomographic bins. The test is rather insensitive to the background cosmology and, therefore, can be implemented before any cosmological inference is made.

Keywords

Cite

@article{arxiv.2009.00367,
  title  = {KiDS+VIKING-450: An internal-consistency test for cosmic shear tomography with a colour-based split of source galaxies},
  author = {Shun-Sheng Li and Konrad Kuijken and Henk Hoekstra and Hendrik Hildebrandt and Benjamin Joachimi and Arun Kannawadi},
  journal= {arXiv preprint arXiv:2009.00367},
  year   = {2021}
}

Comments

12 pages, 8 figures, 3 tables. Revised to match version published in A&A