English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The relation between the mass and integrated electron pressure of galaxygroup and cluster halos can be probed by stacking maps of the thermalSunyaev-Zel'dovich (tSZ) effect. Perhaps surprisingly, recent observationalresults have indicated that the scaling relation between integrated pressureand mass follows the prediction of simple, self-similar models down to halomasses as low as $10^{12.5} \, M_{\odot}$. Hydrodynamical simulations thatincorporate energetic feedback processes suggest that gas should be depletedfrom such low-mass halos, thus decreasing their tSZ signal relative toself-similar predictions. Here, we build on the modeling of Vikram, Lidz, andJain (2017) to evaluate the bias in the interpretation of stacked tSZmeasurements due to the signal from correlated halos (the "two-halo" term),which has generally been neglected in the literature. We fit theoretical modelsto a measurement of the tSZ -- galaxy group cross-correlation function,accounting explicitly for the one- and two- halo contributions. We findmoderate evidence of a deviation from self-similarity in the pressure -- massrelation, even after marginalizing over conservative miscentering effects. Weexplore pressure -- mass models with a break at $10^{14} \, M_{\odot}$, as wellas other variants. We discuss and test for sources of uncertainty in ouranalysis, in particular a possible bias in the halo mass estimates and thecoarse resolution of the Planck beam. We compare our findings with earlieranalyses by exploring the extent to which halo isolation criteria can reducethe two-halo contribution. Finally, we show that ongoing third-generation CMBexperiments will explicitly resolve the one-halo term in low-mass groups; ourmethodology can be applied to these upcoming data sets to obtain a clear answerto the question of self-similarity and an improved understanding of hot gas inlow-mass halos.

The Two-Halo Term in Stacked Thermal Sunyaev-Zel'dovich Measurements: Implications for Self-Similarity