Abstract We present continuum observations from the Atacama Large Millimeter/submillimeter Array of 10 high-redshift (2.2 ≤ z ≤ 2.7) ultraluminous quasars (QSOs) and constrain the presence of hot, ionized, circumgalactic gas in a stacking analysis. We measure a Compton- y parameter profile with a peak value of (1.7 ± 1.1) × 10 −6 at a radius of ∼50 kpc. We compare our stacked observations to active galactic nucleus feedback wind models and generalized Navarro–Frenk–White pressure profile models to constrain the wind luminosity and halo mass of the stacked QSOs. Our observations constrain the observed average halo mass to M 500 &lt; 1 × 10 13 M ⊙ and the average feedback wind power &lt;1 × 10 12 L ⊙ , which is &lt;1% of the bolometric luminosity of the quasar.

Observational Constraints on Sunyaev–Zeldovich Effect Halos around High-z Quasars