Orateur
Description
Over the past decade, the kinetic SZ effect has emerged as a probe of the distribution of baryons and the large-scale velocity field in the late Universe. Of the several ways to detect it, the so-called Projected-Fields kSZ estimator has the promising characteristic of not being limited to spectroscopic samples of galaxies. The original theoretical formulation of this estimator included approximations that are expected to be valid only at small scales, thus limiting its reach to only probing the baryon distribution and not the cosmological parameters. We rigorously derive the Projected-Fields kSZ estimator without these approximations, and show that this improvement leads to significant scale-dependent differences in the predicted signal for future observations from Simons Observatory and CMB-S4. We show that our improved formulation is a necessary step in order to use this estimator for constraining cosmological parameters, and also for accurately estimating the high signal-to-noise ratio measurements from these future CMB surveys. We explore the cosmological dependence of the improved Projected-Fields estimator and illustrate its potential as a cosmological probe with forecasted constraints on cosmological parameters.
