Dark Radiation and Inflationary Freedom

Abstract

A relaxed primordial power spectrum (PPS) of scalar perturbations arising from inflation can impact the dark radiation constraints obtained from Cosmic Microwave Background and other cosmological measurements. If inflation produces a non-standard PPS for the initial fluctuations, a fully thermalized light sterile neutrino can be favoured by CMB observations, instead of being strongly disfavoured. In the case of a thermal axion, the constraints on the axion mass are relaxed when the PPS is different from the standard power law.

8 pages, 4 figures; to appear in the Proceedings of the TAUP 2015 conference

References in corpus (10)

• The Reactor Antineutrino Anomaly
• Statistical Significance of the Gallium Anomaly
• Features and New Physical Scales in Primordial Observables: Theory and Observation
• Primordial power spectrum from Planck
• Light sterile neutrinos after BICEP-2
• Pre - Inflationary Clues from String Theory ?
• Large Short-Baseline antinu_mu Disappearance
• Light Sterile Neutrinos and Inflationary Freedom
• Primordial Power Spectrum features and $f_{NL}$ constraints
• Robustness of cosmological axion mass limits