Pair Creation of Massless Fermions in Electric Flux Tube

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 $Q_s$.