time				envelope	
period	arrivals departures	ray/coeff
   1	   4	    2		 y 24 - x 18
   2	   6	    4		 y 19 - x 18
   3	   17	    23		 y 24 - x 17
   4	   32	    23		ray 25.612826
   5	   33	    46		ray 25.185676
   6	   12	    8		ray 25.019716
   7	   10	    8		 y 18 - x 19
   8	   13	    18		ray 22.429108
   9	   29	    3		ray 23.779337
   10	   22	    5		ray 23.342441
   11	   27	    18		 y 18 - x 17
   12	   14	    29		ray 22.185738
   13	   20	    32		 y 17 - x 23
   14	   9	    10		ray 23.903111
   15	   17	    9		ray 24.175301
   16	   27	    12		ray 23.897542
   17	   22	    20		ray 25.598486
   18	   13	    15		ray 22.631684
   19	   29	    24		 y 19 - x 19
   20	   16	    13		ray 24.214145
   21	   20	    17		ray 24.638790
   22	   13	    6		ray 21.431124
   23	   19	    17		ray 22.993397
   24	   28	    24		ray 22.669415
   25	   7	    21		ray 24.189224
