Comparison of the absorption spectra generated using SOAPv4 for a solar analog hosting a hot Jupiter. The top panel presents a comparison of the absorption profiles obtained using input spectra from IAG, TS, and PHNX spectra that matched the stellar properties. The bottom panel illustrates the differences between the absorption spectrum produced with IAG and the spectra derived from the other models. These simulations represent the POLDs centered on the Na I D₁ line and span a wavelength range of 1 Å on either side.