Constraining brane inflationary magnetic field from cosmoparticle physics after Planck

TL;DR

This paper investigates how cosmological and particle physics constraints, including recent Planck data, limit brane inflationary models and their magnetic fields, linking primordial gravitational waves to baryogenesis and leptogenesis.

Contribution

It establishes new bounds on brane inflationary magnetic fields, reheating parameters, and connects these to observable cosmological data within the RSII framework.

Findings

Constraints on large and small field inflation models from Planck data.

Derived bounds on reheating energy scale and equation of state parameter.

Demonstrated the connection between primordial gravity waves and baryon asymmetry.

Abstract

In this article, I have studied the cosmological and particle physics constraints on a generic class of large field ($|\Delta\phi|>M_{p}$) and small field ($|\Delta\phi<M_{p}$) models of brane inflationary magnetic field from: (1) tensor-to-scalar ratio ($r$), (2) reheating, (3) leptogenesis and (4) baryogenesis in case of Randall-Sundrum single braneworld gravity (RSII) framework. I also establish a direct connection between the magnetic field at the present epoch ($B_{0}$) and primordial gravity waves ($r$), which give a precise estimate of non-vanishing CP asymmetry ($\epsilon_{CP}$) in leptogenesis and baryon asymmetry ($\eta_{B}$) in baryogenesis scenario respectively. Further assuming the conformal invariance to be restored after inflation in the framework of RSII, I have explicitly shown that the requirement of the sub-dominant feature of large scale coherent magnetic field after inflation gives two fold non-trivial characteristic constraints- on equation of state parameter ($w$) and the corresponding energy scale during reheating ($\rho^{1/4}_{rh}$) epoch. Hence giving the proposal for avoiding the contribution of back-reaction from the magnetic field I have established a bound on the generic reheating characteristic parameter ($R_{rh}$) and its rescaled version ($R_{sc}$), to achieve large scale magnetic field within the prescribed setup and further apply the CMB constraints as obtained from recently observed Planck 2015 data and Planck+BICEP2+Keck Array joint constraints. Using all these derived results I have shown that it is possible to put further stringent constraints on various classes of large and small field inflationary models to break the degeneracy between various cosmological parameters within the framework of RSII. Finally, I have studied the consequences from two specific models of brane inflation- monomial and hilltop.