(a) The cylindrical autopower spectrum of the Stokes V mode calculated from the z = 0.44 data (odd-scan cube). (b) Simulated thermal noise autopower spectrum averaged across 10,000 realizations. (c) The 1D autopower spectrum of the Stokes V mode compared against the thermal noise simulation for z = 0.32. (d) Same as panel (c), but for z = 0.44.