On the abundance of primordial bound states of superheavy magnetic monopoles

TL;DR

This paper investigates the survival of primordial bound states of superheavy magnetic monopoles, concluding that interactions with early universe plasma prevent their long-term existence, affecting their potential as sources of ultra-high energy cosmic rays.

Contribution

It demonstrates that primordial bound pairs of magnetic monopoles larger than 10^{-9} cm rapidly thermolise, establishing their equilibrium abundance as the dominant factor.

Findings

Primordial monopole pairs larger than 10^{-9} cm thermolise quickly.

Primordial plasma interactions wash out initial monopole concentrations.

Final monopole abundance is determined by equilibrium conditions.

Abstract

It has been suggested that superheavy charged particles might have been born in primordial bound pairs at the end of cosmic inflation. Such pairs have been proposed as a source of ultra-high energy cosmic rays (UHECR). We show that primordial bound pairs of magnetic monopoles larger than $10^{-9}$ cm quickly thermolise due to the interaction with primordial electron-positron plasma and any such initial primordial concentration is washed out. The final concentration will therefore be defined by their equilibrium abundance.