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Right-handed neutrinos as the source of density perturbations

Lotfi Boubekeur·Paolo Creminelli
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Abstract

We study the possibility that cosmological density perturbations are generated by the inhomogeneous decay of right-handed neutrinos. This will occur if a scalar field whose fluctuations are created during inflation is coupled to the neutrino sector. Robust predictions of the model are a detectable level of non-Gaussianity and, if standard leptogenesis is the source of the baryon asymmetry, a baryon isocurvature perturbations at the level of the present experimental constraints.

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Lotfi Boubekeur, Paolo Creminelli. 2006-02-06. Right-handed neutrinos as the source of density perturbations. https://doi.org/10.1103/physrevd.73.103516

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