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 study the statistics of peaks in a weak lensing reconstructed mass map ofthe first 450 square degrees of the Kilo Degree Survey. The map is computedwith aperture masses directly applied to the shear field with an NFW-likecompensated filter. We compare the peak statistics in the observations withthat of simulations for various cosmologies to constrain the cosmologicalparameter $S_8 = \sigma_8 \sqrt{\Omega_{\rm m}/0.3}$, which probes the($\Omega_{\rm m}, \sigma_8$) plane perpendicularly to its main degeneracy. Weestimate $S_8=0.750\pm0.059$, using peaks in the signal-to-noise range $0 \leq{\rm S/N} \leq 4$, and accounting for various systematics, such asmultiplicative shear bias, mean redshift bias, baryon feedback, intrinsicalignment, and shear-position coupling. These constraints are $\sim25\%$tighter than the constraints from the high significance peaks alone ($3 \leq{\rm S/N} \leq 4$) which typically trace single-massive halos. Thisdemonstrates the gain of information from low-S/N peaks. However we find thatincluding ${\rm S/N} < 0$ peaks does not add further information. Our resultsare in good agreement with the tomographic shear two-point correlation functionmeasurement in KiDS-450. Combining shear peaks with non-tomographicmeasurements of the shear two-point correlation functions yields a $\sim20\%$improvement in the uncertainty on $S_8$ compared to the shear two-pointcorrelation functions alone, highlighting the great potential of peaks as acosmological probe.

KiDS-450: Cosmological Constraints from Weak Lensing Peak Statistics - II: Inference from Shear Peaks using N-body Simulations