Improving reddening estimates for RR Lyrae

Intrinsic colors (G-G_RP_)0 and (G_BP_-G_RP_)0 were derived through sequential feature selection combined with linear regression and bootstrap resampling, ensuring statistically consistent estimates of color excess and A_G_. We recalibrated PACZ relations for RRab stars and derived, for the first time, PAC relations for RRc stars in the Gaia bands. The new relations reproduce intrinsic colors with residual scatters of ~0.03-0.04mag and provide A_G_ estimates across both pulsation types.

Tests on RR Lyrae stars in the MW field, globular clusters, and dwarf galaxy companions show consistent A_G_ values, with the PAC(Z) relations based on (G_BP_-G_RP_) appearing more reliable than those using (G-G_RP_). The new relations provide consistent extinction estimates for both RRab and RRc stars, improving on the DR3 implementation and offering a valuable tool for Galactic studies and cosmic-distance scale work in view of Gaia DR4.