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arXiv · 1411.5256

Primordial non-Gaussian signatures in CMB polarization

Vidhya Ganesan·Pravabati Chingangbam·K. P. Yogendran·Changbom Park
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Abstract

We study the signatures of local type primordial non-Gaussianity, parametrized by $\fnl$, of scalar perturbations in CMB polarization using the probability distribution functions, Minkowski Functionals and Betti numbers. We show that the lowest order non-Gaussian deviation of the PDF of the total polarization intensity is at order $(\fnlσ)^2$. We calculate the non-Gaussian deviations of Minkowski Functionals and Betti numbers from simulated polarization maps. We find that $E$ mode polarization provides independent and equally strong constraint on $\fnl$ as temperature fluctuations. The non-Gaussian signal in the total polarization intensity, however, is much weaker and has a relatively large cosmic variance and hence may not be useful for detecting local type non-Gaussianity.

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Vidhya Ganesan, Pravabati Chingangbam, K. P. Yogendran, Changbom Park. 2014-11-19. Primordial non-Gaussian signatures in CMB polarization. https://doi.org/10.1088/1475-7516%2F2015%2F02%2F028

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