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The Thermal Sunyaev-Zeldovich Effect from Massive, Quiescent 0.5 $leq$ z $leq$ 1.5 Galaxies

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 نشر من قبل Jeremy Meinke
 تاريخ النشر 2021
  مجال البحث فيزياء
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We use combined South Pole Telescope (SPT)+Planck temperature maps to analyze the circumgalactic medium (CGM) encompassing 138,235 massive, quiescent 0.5 $leq$ z $leq$ 1.5 galaxies selected from data from the Dark Energy Survey (DES) and Wide-Field Infrared Survey Explorer (WISE). Images centered on these galaxies were cut from the 1.85 arcmin resolution maps with frequency bands at 95, 150, and 220 GHz. The images were stacked, filtered, and fit with a gray-body dust model to isolate the thermal Sunyaev-Zeldovich (tSZ) signal, which is proportional to the total energy contained in the CGM of the galaxies. We separate these $M_{star} = 10^{10.9} M_odot$ - $10^{12} M_odot$ galaxies into 0.1 dex stellar mass bins, detecting tSZ per bin up to $5.6sigma$ and a total signal-to-noise ratio of $10.1sigma$. We also detect dust with an overall signal-to-noise ratio of $9.8sigma$, which overwhelms the tSZ at 150GHz more than in other lower-redshift studies. We correct for the $0.16$ dex uncertainty in the stellar mass measurements by parameter fitting for an unconvolved power-law energy-mass relation, $E_{rm therm} = E_{rm therm,peak} left(M_star/M_{star,{rm peak}} right)^alpha$, with the peak stellar mass distribution of our selected galaxies defined as $M_{star,{rm peak}}= 2.3 times 10^{11} M_odot$. This yields an $E_{rm therm,peak}= 5.98_{-1.00}^{+1.02} times 10^{60}$ erg and $alpha=3.77_{-0.74}^{+0.60}$. These are consistent with $z approx 0$ observations and within the limits of moderate models of active galactic nuclei (AGN) feedback. We also compute the radial profile of our full sample, which is similar to that recently measured at lower-redshift by Schaan et al. (2021).



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