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Title: Sunyaev–Zeldovich Signals from L* Galaxies: Observations, Analytics, and Simulations
Abstract

We analyze measurements of the thermal Sunyaev–Zeldovich (tSZ) effect arising in the circumgalactic medium (CGM) ofL* galaxies, reported by J. N. Bregman et al. (B+22) and S. Das et al. (D+23). In our analysis, we use the Y. Faerman et al. CGM models, a new power-law model (PLM), and the TNG100 simulation. For a givenMvir, our PLM has four parameters: the fraction,fhCGM, of the halo baryon mass in hot CGM gas, the ratio,ϕT, of the actual gas temperature at the virial radius to the virial temperature, and the power-law indices,aP,thandanfor the thermal electron pressure and the hydrogen nucleon density. The B+22 Compton-yprofile implies steep electron pressure slopes (aP,th≃ 2). For isothermal conditions, the temperature is at least 1.1 × 106K, with a hot CGM gas mass of up to 3.5 × 1011Mfor a virial mass of 2.75 × 1012M. However, if isothermal, the gas must be expanding out of the halos. An isentropic equation of state is favored for which hydrostatic equilibrium is possible. The B+22 and D+23 results are consistent with each other and with recent (0.5–2 keV) CGM X-ray observations of Milky Way mass systems. ForMvir≃ 3 × 1012M, the scaled Compton pressure integrals,E(z)2/3Y500/Mvir,125/3, lie in the narrow range, 2.5 × 10−4–5.0 × 10−4kpc2, for all three sets of observations. TNG100 underpredicts the tSZ parameters by factors ∼0.5 dex for theL* galaxies, suggesting that the feedback strengths and CGM gas losses are overestimated in the simulated halos at these mass scales.

 
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PAR ID:
10549542
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
974
Issue:
2
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 291
Size(s):
Article No. 291
Sponsoring Org:
National Science Foundation
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