Example of template completion using a binary telluric mask. Upper and middle panels: small section of the telluric binary mask for two observations after the correction for Earth’s barycentric motion. Wavelength ranges with y = 1 are masked as tellurics. Lower panel: resulting mask of the template. The red shaded wavelength ranges correspond to template knots with M_k = 0 and contribute to the total masked template fraction γ. The blue shaded wavelength ranges are used for telluric modeling and contribute to γ′.