Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 2511.12488

The first AKRA mass map reconstruction from HSC Y1 data

Yuan Shi·Pengjie Zhang·Zhao Chen·Jian Qin·Li Cui·Furen Deng·Ji Yao
View original source ↗Read source document ↗Export metadata ↓

Abstract

Weak lensing mass-mapping from shear catalogs faces systematic challenges from survey masks and spatially varying noise. To overcome these issues and reconstruct unbiased convergence $κ$ maps, we have constructed the AKRA (Accurate Kappa Reconstruction Algorithm), a prior-free and maximum-likelihood based analytical method. It has been validated for mock shear catalogs with a variety of survey masks. In this work, we present the first real-data application of the AKRA on the Subaru Hyper Suprime-Cam Year 1 (HSC Y1) data. We first validate AKRA using mock shear catalogs from the \texttt{Kun} simulation suite, with masks corresponding to the six HSC Y1 regions (\texttt{GAMA09H}, \texttt{GAMA15H}, \texttt{HECTOMAP}, \texttt{VVDS}, \texttt{WIDE12H}, and \texttt{XMMLSS}). The investigated statistics, including the lensing power spectrum, $\langle κ^2\rangle$, $\langle κ^3\rangle$, and the one-point probability distribution function of $κ$, are all unbiased. We then apply AKRA to the HSC Y1 shear catalog and provide reconstructed $κ$ maps ready for subsequent scientific analyses.

Explore related subjects

astro-ph.CO

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Yuan Shi, Pengjie Zhang, Zhao Chen, Jian Qin, Li Cui, Furen Deng, Ji Yao. 2026-04-22. The first AKRA mass map reconstruction from HSC Y1 data. https://arxiv.org/abs/2511.12488

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Large primordial non-Gaussianity from transient turns in Higgs-$R^2$ inflation

We investigate the generation of primordial non-Gaussianities in multifield Higgs--$R^2$ inflation, focusing on the effects of transient turning trajectories in the hyperbolic field space manifold. We compute the full bispectrum without relying on slow-roll or local approximations and follow the complete superhorizon evolution of curvature and isocurvature perturbations. We show that transient turns efficiently transfer isocurvature fluctuations into the adiabatic sector, generating sizeable local non-Gaussianities. For a benchmark Higgs nonminimal coupling $ξ_h = 0.1$ and quartic coupling $λ= 10^{-10}$, we obtain $f_{\rm NL}^{\rm loc}\simeq -17.7$. As the Higgs nonminimal coupling increases, the turning rate is progressively suppressed and the model approaches the effective single-field attractor, recovering the Maldacena consistency relation $f_{\rm NL}\rightarrow 0.0159$. Comparing our predictions with current CMB constraints, we find that primordial non-Gaussianity provides a sensitive probe of the Higgs nonminimal coupling and can significantly restrict the viable parameter space of the model.

astro-ph.CO↗
arXiv2026

From quantum fluctuations to galaxy power spectrum multipoles

These notes trace large-scale structure from primordial curvature perturbations generated by inflationary quantum fluctuations to galaxy power-spectrum multipoles. Three core lectures develop the linear matter power spectrum, spherical and anisotropic collapse, galaxy bias, redshift-space distortions, the Kaiser model, and multipole estimators with Gaussian covariance. The extension develops nonlinear bias and the one-loop effective field theory model used in full-shape analyses. Derivations are explicit; appendices collect longer calculations and solutions. The core lectures assume undergraduate-level cosmology; the extension assumes familiarity with perturbation theory.

astro-ph.CO↗
arXiv2026

A universal connection between lens density profiles and low-frequency wave optics in gravitational-wave lensing

We investigate the low-frequency behavior of the amplification factor in gravitational lensing and explore how it encodes information about the density profile of the lensing object. We derive the low-frequency expansion of the amplification factor under the Born approximation for a broad class of projected density profiles. For spherically symmetric profiles that decay faster than any power law at large distances, we derive a systematic expansion of the amplification factor in powers of frequency, with the logarithmic dependence appearing only in the leading term, and show that each expansion coefficient is determined by a finite set of moments of the density profile. We then extend the analysis to profiles with power-law tails and demonstrate that such profiles induce additional non-analytic frequency dependences, including fractional powers and logarithmic terms, which directly reflect the asymptotic behavior of the density distribution. Furthermore, we investigate the effects of non-sphericity and show that contributions from the quadrupole moment appear only as higher-order corrections relative to the spherically symmetric component in the low-frequency regime. Finally, we investigate the validity of the Born approximation in the low-frequency expansion. We derive a criterion for the maximum order of the low-frequency expansion up to which the Born approximation remains dominant over the post-Born corrections.

astro-ph.CO↗