Staggered grid and outputting fields

[asteroi]

Hello,

I am simulating a laser pulse propagating in vacuum right now, and I am specifically interested in the fields and the energy flow. As I understand it, EPOCH performs its calculations with the fields on a staggered grid. Does EPOCH also output the electric and magnetic fields directly from the staggered grid (meaning the Ex, Ey, and Ez values in the output are from different points on each cell)? Similarly, from which points on the cell are each of the Poynting vector components calculated?

On another note, the group velocity of my pulse appears to move faster than c despite being in vacuum. I noticed that this is worse at lower longitudinal resolution (λ/8). Is this just a resolution issue with the default solver, or is there another issue with how I have defined my simulation? Thanks!

inputdeck.txt