2024ApJ...969...56M

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 M₅₀₀ < 1 × 10¹³M_⊙ and the average feedback wind power <1 × 10¹²L_⊙, which is <1% of the bolometric luminosity of the quasar.