English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present updated cosmological constraints for the KiDS+VIKING-450 cosmicshear data set (KV450), estimated using redshift distributions and photometricsamples defined using self-organising maps (SOMs). Our fiducial analysis findsmarginal posterior constraints of $S_8\equiv\sigma_8\sqrt{\Omega_{\rmm}/0.3}=0.716^{+0.043}_{-0.038}$; smaller than, but otherwise consistent with,previous work using this data set ($|\Delta S_8| = 0.023$). We analyseadditional samples and redshift distributions constructed in three ways:excluding certain spectroscopic surveys during redshift calibration, excludinglower-confidence spectroscopic redshifts in redshift calibration, andconsidering only photometric sources which are jointly calibrated by at leastthree spectroscopic surveys. In all cases, the method utilised here provesrobust: we find a maximal deviation from our fiducial analysis of $|\Delta S_8|\leq 0.011$ for all samples defined and analysed using our SOM. To demonstratethe reduction in systematic biases found within our analysis, we highlight ourresults when performing redshift calibration without the DEEP2 spectroscopicdata set. In this case we find marginal posterior constraints of$S_8=0.707_{-0.042}^{+0.046}$; a difference with respect to the fiducial thatis both significantly smaller than, and in the opposite direction to, theequivalent shift from previous work. These results suggest that our improvedcosmological parameter estimates are insensitive to pathologicalmisrepresentation of photometric sources by the spectroscopy used for directredshift calibration, and therefore that this systematic effect cannot beresponsible for the observed difference between $S_8$ estimates made with KV450and Planck CMB probes.

KiDS+VIKING-450: Improved cosmological parameter constraints from redshift calibration with self-organising maps