real pi_
      parameter (pi_=3.1415926)
      real K_,me_c2,c_
      parameter (K_=0.307e6,me_c2=511.e+3,c_=3.0e10)
      real Z_,A_,I_
      parameter (Z_=6,A_=12.01,I_=80.)
      real Cp,kappa,SBc,Tambient
      parameter (Cp=5e5)
      parameter (kappa=10.)
      parameter (SBc=5.67e-12)
      parameter (Tambient=300.)
      real density,refindex,heatcap
      parameter (density=3.52,refindex=2.42,heatcap=1.66)
      real rthick,rwide,rhigh
      real beamsizeX,beamsizeY,hpower
      common /changeables/rthick,rwide,rhigh,
     +                    beamsizeX,beamsizeY,hpower

      integer NX,NY
      parameter (NX=30,NY=30)
      vector Tgrid(30,30)
      real time
      common /thegrid/time