Quark Pair Production in Expanding Glasma

Glasma in high energy heavy ion collisions is longitudinal classical color electric and magnetic fields. The color electric field has been shown to produces quark and anti-quark pairs by the Schwinger mechanism and to oscillate with time in non-expanding glasma, that is, plasma oscillation. On the other hand, in the expanding glasma we show that the field decreases with the plasma oscillation. We can explicitly obtain the solutions representing such temporal behaviors in the system with $\tau$ and $\eta$ coordinates. We show these results by using massless QED as a simplified model of QCD.