UV band spectra at different T_eff and log g. These subplots show the spectra flux under varying T_eff (ranging from 3800 K to 12 000 K) and log g (ranging from +1.0 to +6.0), with [Fe/H] changing from metal-rich ([Fe/H] = +1.0) to EMP ([Fe/H] = −4.0). The red curves generally represent higher [Fe/H], while blue curves represent lower [Fe/H]. The transition from red to blue corresponds to the change from high to low [Fe/H], where each curve represents a specific level of [Fe/H].