A Rich Tapestry: Supersymmetric Axions, Dark Radiation, and Inflationary Reheating

TL;DR

This paper constrains supersymmetric axion models by analyzing their implications on dark radiation, BBN, and CMB, using recent Planck and BICEP data to identify viable parameter regions.

Contribution

It provides a comprehensive analysis combining multiple cosmological constraints to delineate the parameter space of supersymmetric axion models.

Findings

BBN bounds restrict hadronic and electromagnetic energy injection.

CMB data constrains black-body spectrum distortions.

Certain supersymmetric axion models can account for observed dark radiation.

Abstract

We exploit the complementarity among supersymmetry, inflation, axions, Big Bang Nucleosynthesis (BBN) and Cosmic Microwave Background Radiation (CMB) to constrain supersymmetric axion models in the light of the recent Planck and BICEP results. In particular, we derive BBN bounds coming from altering the light element abundances by taking into account hadronic and electromagnetic energy injection, and CMB constraints from black-body spectrum distortion. Lastly, we outline the viable versus excluded region of these supersymetric models that might account for the mild dark radiation observed.