131 citations · 256 across the 3 of their papers we have counts for
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astro-ph2007★ 96 cited
Observational bounds on the cosmic radiation density
Jan Hamann, Steen Hannestad, Georg G. Raffelt +1
We consider the inference of the cosmic radiation density, traditionally parameterised as the effective number of neutrino species N_eff, from precision cosmological data. Paying p…
astro-ph2007★ 131 cited
New Constraints on Oscillations in the Primordial Spectrum of Inflationary Perturbations
Jan Hamann, Laura Covi, Alessandro Melchiorri +1
We revisit the problem of constraining steps in the inflationary potential with cosmological data. We argue that a step in the inflationary potential produces qualitatively similar…