10.6k citations · 29.2k across the 47 of their papers we have counts for
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Using BBN in cosmological parameter extraction from CMB: a forecast for Planck
Jan Hamann, Julien Lesgourgues, Gianpiero Mangano
Data from future high-precision Cosmic Microwave Background (CMB) measurements will be sensitive to the primordial Helium abundance . At the same time, this parameter can be p…
Effects of CMB temperature uncertainties on cosmological parameter estimation
Jan Hamann, Yvonne Y. Y. Wong
We estimate the effect of the experimental uncertainty in the measurement of the temperature of the cosmic microwave background (CMB) on the extraction of cosmological parameters f…
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…
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…