New period-luminosity and period-color relations of classical Cepheids. IV. The low-metallicity galaxies IC 1613, WLM, Pegasus, Sextans A and B, and Leo A in comparison to SMC

The metal-poor, fundamental-mode (P0) and first-overtone (P1) Cepheids in the dwarf galaxies IC 1613, WLM, Pegasus, Sextans A, Sextans B, and Leo A are compared with the about equally metal-poor Cepheids of the Small Magellanic Cloud (SMC). The period-color (P-C) and period-luminosity (P-L) relations of the seven galaxies are indistinguishable, but differ distinctly from those in the Large Magellanic Cloud (LMC) and the solar neighborhood. Adopting (m-M)^0_SMC=18.93 from independent evidence, one can determine reliable distance moduli for the other dwarf galaxies of (m - M)⁰ = 24.34 ± 0.03, 24.95 ± 0.03, 24.87 ± 0.06, 25.60 ± 0.03 (mean for Sextans A & B), and 24.59 ± 0.03, respectively.