Poster Presentation
Development of galaxy power spectrum estimator to mitigate angular systematic effects and its application to the pursuit of primordial non-Gaussianity
Presenter: Shintaro Nakano (Kavli IPMU / The University of Tokyo)
The galaxy power spectrum is a statistical measure rich in cosmological information obtained from spectroscopic galaxy surveys and serves as a powerful tool, particularly for probing primordial non-Gaussianity. Local-type primordial non-Gaussianity induces a scale-dependent linear galaxy bias proportional to $k^{?2}$ even on long-wavelength scales in the linear regime, making it possible to probe through the analysis of the galaxy power spectrum on linear scales. Since the simplest single-field inflation models do not predict detectable local-type primordial non-Gaussianity, its detection in observational data would rule out the single-field inflation scenario, making its impact significant.
However, actual observational data suffer from systematic errors that are difficult to model accurately, such as contamination of galaxy samples by stars in the Milky Way and dust extinction, which distort the galaxy distribution on the celestial sphere. In this study, we develop a method to mitigate the effects of such distortions, particularly those originating from the Milky Way, to accurately measure the galaxy power spectrum in the linear regime. In this talk, I will present an evaluation of the method
asiaa.sinica.edu.tw