MACRO accplot
  exec cobrems coldiam=3.4e-3
  fun1 50 acceptance((x/7600*12/511e-6)**2) 100 0 0.5
  exec cobrems coldiam=5.0e-3
  fun1 51 acceptance((x/7600*12/511e-6)**2) 100 0 0.5
  exec cobrems coldiam=3.4e-1
  fun1 52 acceptance((x/7600*12/511e-6)**2) 100 0 0.5
  set lwid 5
  max 50 1.1
  opt utit
  set fcol 2; h/pl 50
  set fcol 4; set htyp 1; h/pl 51 s
  set fcol 1; set htyp 1; h/pl 52 s
  atit 'projected radius at collimator, ideal (cm)' 'collimator acceptance'
RETURN