Abstract Precise, unbiased measurements of extragalactic background anisotropies require careful treatment of systematic effects in fluctuation-based, broadband intensity mapping measurements. In this paper, we detail improvements in methodology for the Cosmic Infrared Background Experiment (CIBER), concentrating on flat field errors and source masking errors. In order to bypass the use of field differences, which mitigate flat field errors but reduce sensitivity, we characterize and correct for the flat field on pseudopower spectra, which includes both additive and multiplicative biases. To more effectively mask point sources at 1.1 and 1.8 μ m, we develop a technique for predicting masking catalogs that utilizes optical and near-infrared photometry through random forest regression. This allows us to mask over 2 Vega mag deeper than the completeness limits of Two Micron All Sky Survey alone, with errors in the shot noise power remaining below <10% at all masking depths considered. Through detailed simulations of CIBER observations, we validate our formalism and demonstrate unbiased recovery of the sky fluctuations on realistic mocks. We demonstrate that residual flat field errors comprise <20% of the final CIBER power spectrum uncertainty with this methodology.
Feder et al. (Wed,) studied this question.