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DOE OSTI · 22306140

CMB non-gaussianity from vector fields

Peloso, Marco
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Abstract

The Planck satellite has recently measured the CMB temperature anisotropies with unprecedented accuracy, and it has provided strong bounds on primordial non-gaussianity. Such bounds constrain models of inflation, and mechanisms that produce the primordial perturbations. We discuss the non-gaussian signatures from the interactions of the inflation φ with spin-1 fields. We study the two different cases in which the inflaton is (i) a pseudo-scalar field with a (φ)/(fa) F·F interaction with a vector field, and (ii) a scalar field with a f (φ)F² interaction. In the first case we obtain the strong limit f{sub a} ≥ 10¹⁶GeV on the decay constant. In the second case, specific choices of the function f (φ) can lead to a non-gaussianity with a characteristic shape not encountered in standard models of scalar field inflation, and which has also been constrained by Planck.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSACCURACYANISOTROPYPARTICLE DECAYPERTURBATION THEORYSCALAR FIELDSSTANDARD MODELVECTOR FIELDS

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Peloso, Marco. 2014-01-01. CMB non-gaussianity from vector fields. https://doi.org/10.1063/1.4883461

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