SPT-3G D1: Compton-$y$ maps using data from the SPT-3G and Planck surveys

TL;DR

This paper presents high-resolution, low-noise Compton-$y$ maps from SPT-3G and Planck data, validated through statistical tests, enabling advanced cosmological analyses of large-scale structure and baryon thermodynamics.

Contribution

It introduces a suite of tSZ $y$-maps with different foreground suppression techniques, validated for robustness and ready for cosmological applications.

Findings

Validated the $y$-maps using power spectra and stacking techniques.

Confirmed the robustness of the tSZ signal across the survey area.

Produced maps suitable for future cosmological and astrophysical studies.

Abstract

We present thermal Sunyaev-Zel'dovich (tSZ) Compton-$y$ parameter maps constructed from two years (2019-2020) of observations with the South Pole Telescope (SPT) third-generation camera, SPT-3G, combined with data from the Planck satellite. Using a linear combination (LC) pipeline, we obtain a suite of reconstructions that explore different trade-offs between statistical sensitivity and suppression of astrophysical contaminants, including minimum-variance, CMB-deprojected, and CIB-deprojected $y$-maps. We validate these maps through different statistical techniques such as auto- and cross-power spectra with large-scale structure tracers as well as stacking on cluster locations. These tests are used to understand the balance between noise and astrophysical foreground residuals (such as the CIB) in combination with the recovery of the tSZ signal for different maps. For example, results from stacking at the location of clusters confirm the robustness of the recovered tSZ signal over the $\sim 1500\: {\rm deg}^2$ SPT-3G survey field used in this analysis. The high-resolution and low-noise maps produced here provide an important cosmological tool for future studies, including measurements of the Compton-$y$ map power spectrum, cross-correlations with other tracers of the large-scale structure, detailed modeling of cluster pressure profiles, and study of the thermodynamic state of the baryons in the Universe.