Two-dimensional Configuration and Temporal Evolution of Spark Discharges in Pulsars

We have investigated the evolution of a system sparking discharges in inner acceleration region (IAR) above pulsar polar cap. The surface cap is heated to temperatures around $10^6$ K and forms partially screened gap (PSG) due thermionic emission positively charged ions from stellar surface. sparks lag behind co-rotation speed during their lifetimes variable $E$x$B$ drift. In PSG arise locations where go below critical level ($T_i$) for freely flow commences large potential drop developing along magnetic field lines these lower temperature regions subsequently back streaming particles heat $T_i$. regulation requires be tightly filled with continuous presence required its boundary since no heating possible closed line region. estimated time IAR which shows gradual shift spark formation two distinct directions resembling clockwise anti-clockwise motion halves Due differential pattern halves, central develops representing core emission. temporal process was simulated different orientations non-dipolar reproduced diverse observational features associated subpulse drifting.