subroutine write_injection_line_trajectory(s,vec1, vec2, ele_name,ix_end,r,state)
       use bmad
       use parameters_bmad
       implicit none
       real(rp) s, vec1(1:6), vec2(1:6), r(1:3)
       integer, save :: lun71
       integer ix_end
       integer state
       character*16 ele_name
       logical first/.true./


       if(first)then
         lun71 = lunget()
         open(unit=lun71,file=trim(directory)//'/'//'injection_line_trajectory.dat')
         write(lun71,'(a12,1x,7a12)') 's','x','xp','y','yp','z','pz','state'
         first=.false.
       endif

       write(lun71,'(es12.4,1x,6es12.4,1x,6es12.4,1x,a16,1x,i10,1x,3es12.4,1x,i12)')s, vec1, vec2,ele_name, ix_end,r , state
       return
       end