Limb-darkening Coefficients for the Filter CBB

Abstract The CBB filter is particularly appropriate for exoplanet differential photometry using smaller (≤1.0 m) telescopes for two primary reasons. First, the CBB filter provides far greater throughput than standard filters (i.e., 92% throughput for CBB compared to 19% for V), which results in significantly greater measurement precision. Second, the CBB significantly reduces the size of air-mass curvature systematic error (8 mmag/airmass for a CBB filter compared to 59 mmag/airmass for a clear filter). In this Research Note we provide the theoretical calculations of the limb-darkening coefficients (LDCs) for the filter CBB adopting the two most used bi-parametric laws: quadratic and power-2 laws. The calculations of LDCs were carried out adopting the ATLAS stellar atmosphere models, plane-parallel version. These grids cover 19 metallicities ranging from 10−5 up to 10 +1 solar abundances, 0 ≤ log g ≤ 5.0 and 3500 K ≤ T eff ≤ 50,000 K (9586 models).