The Frequency Spectrum of the Thermal Decrement from Thirty to Three Hundred Gigahertz, Computed for Survey Band Planning

This paper computes a specific Sunyaev-Zel'dovich observable for hot intracluster gas in a cosmology whose early expansion is regulated by a high-density bounce, and compares the result with published measurements from Planck, the Atacama Cosmology Telescope and the South Pole Telescope. The headline computed values are: dT_150 = -260; dT_90 = -435; dT_30 = -532. The bounce correction to the expansion rate at cluster redshifts is evaluated exactly from the stated density bound rather than neglected, and its size is reported alongside the observable. Where the correction falls far below the scatter of present measurements, that negative result is stated plainly: this observable, at current precision, does not distinguish the bounce frame from the standard expansion history. All numbers are computed from the stated assumptions in the accompanying code; nothing here is a new measurement.