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arXiv · 2205.14408

Constraints on $\tau_\mathrm{NL}$ from Planck temperature and polarization

Kareem Marzouk·Antony Lewis·Julien Carron
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Abstract

We update constraints on the amplitude of the primordial trispectrum, using the final Planck mission temperature and polarization data. In the squeezed limit, a cosmological local trispectrum would be observed as a spatial modulation of small-scale power on the CMB sky. We reconstruct this signal as a source of statistical anisotropy via quadratic estimator techniques. We systematically demonstrate how the estimated power spectrum of a reconstructed modulation field can be translated into a constraint on $\tau_\mathrm{NL}$ via likelihood methods, demonstrating the procedures effectiveness by inferring known $\tau_\mathrm{NL}$ signal(s) from simulations. Our baseline results constrain $\tau_\mathrm{NL} < 1700$ at the 95\% confidence level, providing the most stringent constraints to date.

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Kareem Marzouk, Antony Lewis, Julien Carron. 2022-05-28. Constraints on $\tau_\mathrm{NL}$ from Planck temperature and polarization. https://doi.org/10.1088/1475-7516%2F2022%2F08%2F015

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