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arXiv · 2607.11254

Cosmology from Nx2pt Analyses of SKAO Wide-Area Surveys

Ian Harrison·Ziad Sakr·Giulia Piccirilli·Chandra Shekhar Saraf·Jacobo Asorey·Benedict Bahr-Kalus·José Fonseca·Marina Migliaccio·David Parkinson·Cora Uhlemann
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Abstract

SKAO surveys will provide an unprecedented window into the large-scale structure of the universe through HI 21cm galaxy and intensity mapping surveys, and radio continuum surveys. We present forecasts for the cosmological constraining power of ``$N\times2\mathrm{pt}$'' analyses -- which combine galaxy clustering, galaxy weak lensing, galaxy-galaxy lensing signals and 21cm Intensity Maps. By assuming cosmology surveys from an SKA-Mid AA4, we show that such an $N\times2\mathrm{pt}$ analysis will be able to deliver measurements of $\sim1\%$ precision on $\Lambda$CDM cosmological parameters. We also explore dynamical dark energy in the $w_0, w_a$ model, the sum of neutrino masses $\rm M_\nu$, and the background curvature $\Omega_{\rm k}$.

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Ian Harrison, Ziad Sakr, Giulia Piccirilli, Chandra Shekhar Saraf, Jacobo Asorey, Benedict Bahr-Kalus, José Fonseca, Marina Migliaccio, David Parkinson, Cora Uhlemann. 2026-07-13. Cosmology from Nx2pt Analyses of SKAO Wide-Area Surveys. https://arxiv.org/abs/2607.11254

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