Thermal energy census with the Sunyaev-Zel'dovich effect of DESI galaxy clusters/groups and its implication on the weak lensing power spectrum

Abstract

We carry out a thermal energy census of hot baryons at 𝑧 < 1, by cross-correlating the Planck MILCA y-map with over 40 DESI galaxy cluster/group subsamples constructed from the Yang et. al ( 2021) catalog. In our investigation, we select 0.8 million clusters/groups with richness ≥ 5 and estimated halo mass ≥ 10 13 𝑀 /ℎ. The detection of the thermal Sunyaev-Zel'dovich (tSZ) effect is significant in the investigated clusters/groups. (1) The total measurement S/N of the one-halo term is 65. We constrain the 𝑌 − 𝑀 relation over the halo mass range of 10 13 − 10 15 𝑀 /ℎ. We find 𝑌 ∝ 𝑀 𝛼 with 𝛼 = 1.8 at 𝑧 = 0.14 and 𝛼 = 2.1 at 𝑧 = 0.75. The total thermal energy of gas bound to clusters/groups increases from 0.11meV/cm 3 at 𝑧 = 0.14 to 0.23meV/cm 3 at 𝑧 = 0.75. (2) The two-halo term measurement constrains the bias-weighted electron pressure 𝑏 𝑦 𝑃 𝑒 . We find that 𝑏 𝑦 𝑃 𝑒 (in unit of meV/cm 3 ) increases from 0.25 ± 0.03 at 𝑧 = 0.14 to 0.55 ± 0.04 at 𝑧 = 0.75. These results lead to several implications. (i) The hot gas fraction 𝑓 gas in clusters/groups monotonically increase with halo mass, where 𝑓 gas of a 10 14 𝑀 /ℎ halo is ∼ 50% (20%) of the cosmic mean at 𝑧 = 0.14 (0.75). (ii) By comparing the 1h-and 2h-terms, we constrain the thermal energy of unbound gas. (iii) The above results lead to a suppression of matter and weak lensing power spectrum. At 𝑙 = 10 3 (10 4 ), the suppression is ∼ 7% (17%) for source galaxies at 𝑧 𝑠 = 1. These implications are potentially important for gastrophysics and cosmology, although they suffer from uncertainties in measurements (Planck resolution, cluster mass/redshift determination, etc) and gas modeling to be further investigated.

Understanding the Sunyaev-Zeldovich decrement versus halo mass using the SIMBA and TNG Simulations

“…For instance, the DESI sample at higher redshifts is weighted towards more massive objects, and hence this measurements conflates the (opposite) effects of redshift evolution and halo mass dependence. Given that we have found a strong dependence of the measured 𝑌 − 𝑀 relation on observational selection and analysis methodology, we leave a more careful comparison to Chen et al (2022)…”

“…Note that their result is mostly from the massive galaxy clusters. Recently, by measuring the stacked tSZ signal around DESI galaxy clusters/groups using the Planck SZ 𝑦-map, Chen et al (2022) found a slightly steeper 𝑌 − 𝑀 slope than the self-similar model, which also has a slight tendency of increase with redshift.…”

\textsc{The Three Hundred} project: The \textsc{Gizmo-Simba} run

“…Statistical or best-fit results are presented for Lovisari et al (2015); Eckert et al (2016); Dietrich et al (2019) since these do not provide individual cluster data. Note that other works, such as Lin & Mohr (2004); Gonzalez et al (2007); Andersson et al (2011); Budzynski et al (2014) and also the recent works Lim et al (2020); Chen et al (2022) (estimating gas fractions with SZ signal instead of X-ray) that also examined clusters at 𝑧 ∼ 0.1 to investigate similar fractions, are not included in this comparison due to different reasons, such as no 𝑀 500 or 𝑀 * being available, or that the sample is dominated by 𝑧 0 clusters. However, it has been suggested that there is almost no redshift evolution in both gas and stellar fractions within 𝑧 ∼ 1 (see more discussion below), so we include the best fitting results from the recent work of Akino et al (2021) out to modest redshifts using weak-lensing masses (Umetsu et al 2020) for the 136 XXL clusters in the HSC-SSP survey, shown as the grey shaded band.…”

Constraining the Baryonic Feedback with Cosmic Shear Using the DES Year-3 Small-Scale Measurements

“…Ref. [72] used thermal Sunyaev-Zeldovich map from Planck around stacked DESI catalog to explore the baryonic feedback. They found β to be always positive, which is consistent with our analysis choice of fixing β = 0.321,; their constraint on M c also agrees with our findings.…”