Observing the Universe at millimetre wavelengths

Constraints on primordial non-Gaussianity from halo bias measured through CMB lensing cross-correlations

28 juin 2023, 15:00

20m

Amphitheatre (LPSC Grenoble)

Wednesday P1

Orateur

Fiona McCarthy (Flatiron Institute)

Description

Local primordial non-Gaussianity, parametrized by $f_{NL}^{\mathrm{loc}}$, induces a characteristic scale dependence in the large-scale bias of halos. This scale dependence is a promising path to constrain multi-field inflation theories, which predict non-zero $f_{NL}^{\mathrm{loc}}$. We use the cosmic infrared background (CIB), measured by $\mathit{\text{Planck}}$, which is sourced by thermal emission from dust grains in star-forming galaxies, to constrain the scale dependent bias and thus $f_{NL}^{\mathrm{loc}}$. As the CIB is difficult to separate from the dust emission in our own galaxy, we use the cross-correlation with the CMB lensing map of $\mathit{\text{Planck}}$ to isolate the cosmological signal and thus use only information from the cross power spectra $C_{\ell }^{\nu \kappa }$ on large scales. We find no evidence for primordial non-Gaussianity and find $−87

Documents de présentation

McCarthy_Grenoble5.pdf