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arXiv · 1711.08286

CMB constraints on running non-Gaussianity

Filippo Oppizzi·Michele Liguori·Alessandro Renzi·Frederico Arroja·Nicola Bartolo
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Abstract

We develop a complete set of tools for CMB forecasting, simulation and estimation of primordial running bispectra, arising from a variety of curvaton and single-field (DBI) models of Inflation. We validate our pipeline using mock CMB running non-Gaussianity realizations and test it on real data by obtaining experimental constraints on the $f_{\rm NL}$ running spectral index, $n_{\rm NG}$, using WMAP 9-year data. Our final bounds (68\% C.L.) read $-0.6< n_{\rm NG}<1.4$, $-0.3< n_{\rm NG}<1.2$, $-1.1<n_{\rm NG}<0.7$ for the single-field curvaton, two-field curvaton and DBI scenarios, respectively. We show forecasts and discuss potential improvements on these bounds, using {\it Planck} and future CMB surveys.

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Filippo Oppizzi, Michele Liguori, Alessandro Renzi, Frederico Arroja, Nicola Bartolo. 2017-11-22. CMB constraints on running non-Gaussianity. https://doi.org/10.1088/1475-7516%2F2018%2F05%2F045

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