Pair Creation of Massless Fermions in Electric Flux Tube

TL;DR

This paper analyzes the rapid decay of electric flux tubes due to massless fermion pair creation in strong magnetic fields, with implications for the evolution of glasma in heavy-ion collisions.

Contribution

It provides an analytical study of fermion pair creation in electric flux tubes under magnetic fields, revealing how tube width affects electric field lifetime.

Findings

Electric field lifetime decreases with narrower flux tubes.

In strong magnetic fields, the electric field decays rapidly, approximately as the inverse of the saturation momentum.

Analytical solutions describe spatial and temporal behavior of generated fields.

Abstract

Using chiral anomaly, we discuss the pair creation of massless fermions in an electric flux tube $\vec{E}$ under homogeneous magnetic field $\vec{B}$ parallel to $\vec{E}$. The tube is axial symmetric and infinitely long in longitudinal direction. In the limit $B\gg E$, we can analytically obtain the spatial and temporal behaviors of the electric field and azimuthal magnetic field generated by the produced fermions. We find that the life time $t_c$ of the electric field is shorter as the width of the tube is narrower. Applying it to the glasma in high-energy heavy-ion collisions, we find that color electric field decays fast such as $t_c\simeq Q_s^{-1}$ with saturation momentum $Q_s$.