Constraints on primordial magnetic fields from magnetically-induced perturbations: current status and future perspectives with LiteBIRD and future ground based experiments

TL;DR

This paper reviews current constraints on primordial magnetic fields using CMB data and forecasts the potential improvements with upcoming experiments like LiteBIRD and ground-based observatories.

Contribution

It updates previous Planck 2015 constraints on primordial magnetic fields and provides forecasts for future CMB experiments' capabilities.

Findings

Current CMB data constrains magnetic field amplitude.

Forecasts show improved sensitivity with LiteBIRD and ground-based experiments.

No assumptions made on the origin of magnetic fields.

Abstract

We present the constraints on the amplitude of magnetic fields generated prior to the recombination using CMB temperature and polarization anisotropy data from Planck 2018 release, alone and in combination with those from BICEP2/Keck array and the South Pole Telescope. We model the fields with a generic parametrization and we make no assumptions on their origin in order to provide general constraints on their characteristics. The analysis updates the former corresponding Planck 2015 results both on data and numerical implementation. We then perform forecasts for the next generation of CMB experiments such as LiteBIRD satellite alone and in combination with future ground based experiments.