{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/kids-viking-450-and-des-y1-combined-cosmology","title":"KiDS+VIKING-450 and DES-Y1 combined: Cosmology with cosmic shear","arxiv_id":"1906.09262","date":"2019-06-21","proceeding":null,"authors":["S. Joudaki","H. Hildebrandt","D. Traykova","N. E. Chisari","C. Heymans","A. Kannawadi","K. Kuijken","A. H. Wright","M. Asgari","T. Erben","H. Hoekstra","B. Joachimi","L. Miller","T. Tröster","J. L. van den Busch"],"abstract":"We present a combined tomographic weak gravitational lensing analysis of the Kilo Degree Survey (KV450) and the Dark Energy Survey (DES-Y1). We homogenize the analysis of these two public cosmic shear datasets by adopting consistent priors and modeling of nonlinear scales, and determine new redshift distributions for DES-Y1 based on deep public spectroscopic surveys. Adopting these revised redshifts results in a $0.8\\sigma$ reduction in the DES-inferred value for $S_8$, which decreases to a $0.5\\sigma$ reduction when including a systematic redshift calibration error model from mock DES data based on the MICE2 simulation. The combined KV450 + DES-Y1 constraint on $S_8 = 0.762^{+0.025}_{-0.024}$ is in tension with the Planck 2018 constraint from the cosmic microwave background at the level of $2.5\\sigma$. This result highlights the importance of developing methods to provide accurate redshift calibration for current and future weak lensing surveys.","url_abs":"https://arxiv.org/abs/1906.09262v2","url_pdf":"https://arxiv.org/pdf/1906.09262v2.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"kids-viking-450-and-des-y1-combined-cosmology","repo_url":"https://github.com/sjoudaki/kidsdes","is_official":0,"mentioned_in_paper":0,"mentioned_in_github":1,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}