First Constraints from Marked Angular Power Spectra with Subaru Hyper Suprime-Cam Survey First-Year Data

TL;DR

This paper introduces marked angular power spectra for weak lensing analysis, demonstrating improved constraints on cosmological parameters and robustness against systematics using Subaru HSC-Y1 data.

Contribution

It is the first application of marked power spectra to weak lensing data, showing enhanced parameter constraints and systematic sensitivity analysis.

Findings

Marked spectra improve $S_8$ constraints by ~43% over standard methods.

Applied to Subaru HSC-Y1 data, resulting in $S_8=0.807\u00b10.024$.

Marked statistics show promise for extracting non-Gaussian information.

Abstract

We present the first application of marked angular power spectra to weak lensing data, using maps from the Subaru Hyper Suprime-Cam Year 1 (HSC-Y1) survey. Marked convergence fields, constructed by weighting the convergence field with non-linear functions of its smoothed version, are designed to encode higher-order information while remaining computationally tractable. Using simulations tailored to the HSC-Y1 data, we test three mark functions that up- or down-weight different density environments. Our results show that combining multiple types of marked auto- and cross-spectra improves constraints on the clustering amplitude parameter $S_8\equiv\sigma_8\sqrt{\Omega_{\rm m}/0.3}$ by $\approx$43\% compared to standard two-point power spectra. When applied to the HSC-Y1 data, this translates into a constraint on $S_8 = 0.807\pm 0.024$. We assess the sensitivity of the marked power spectra to systematics, including baryonic effects, intrinsic alignment, photometric redshifts, and multiplicative shear bias. These results demonstrate the promise of marked statistics as a practical and powerful tool for extracting non-Gaussian information from weak lensing surveys.