Detecting deviations from Gaussianity in high-redshift CMB lensing maps by Zhuoqi Zhang et al. on Monday 21 November
While the probability density function (PDF) of the cosmic microwave
background (CMB) convergence field approximately follows a Gaussian
distribution, small contributions from structures at low redshifts make the
overall distribution slightly non-Gaussian. Some of this late-time component
can be modelled using the distribution of galaxies and subtracted off from the
original CMB lensing map to produce a map of matter distribution at high
redshifts. Using this high-redshift mass map, we are able to directly study the
early phases of structure formation and look for deviations from our standard
model. In this work, we forecast the detectability of signatures of
non-Gaussianity due to nonlinear structure formation at $z>1.2$. Although we
find that detecting such signatures using ongoing surveys will be challenging,
we forecast that future experiments such as the CMB-S4 will be able to make
detections of $\sim$ 7$\sigma$.
arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.09617v1
