time				envelope	
period	arrivals departures	ray/coeff
   1	   4	    5		 y 23 - x 17
   2	   6	    3		 y 20 - x 20
   3	   17	    13		ray 21.830447
   4	   32	    26		ray 23.512225
   5	   33	    44		ray 23.506386
   6	   12	    13		ray 23.633858
   7	   10	    8		ray 22.408843
   8	   13	    19		ray 24.101161
   9	   29	    4		 y 20 - x 25
   10	   22	    5		ray 22.161448
   11	   27	    16		 y 23 - x 19
   12	   14	    30		 y 25 - x 19
   13	   20	    34		ray 23.719172
   14	   9	    12		 y 18 - x 24
   15	   17	    9		ray 26.168773
   16	   27	    13		ray 21.790853
   17	   22	    25		ray 22.897510
   18	   13	    18		 y 20 - x 18
   19	   29	    19		ray 25.495521
   20	   16	    12		 y 17 - x 23
   21	   20	    14		ray 23.770873
   22	   13	    8		 y 18 - x 18
   23	   19	    23		 y 24 - x 18
   24	   28	    25		 y 18 - x 24
   25	   22	    21		ray 25.486121
   26	   25	    10		ray 24.000038
   27	   19	    26		ray 24.129504
   28	   15	    17		 y 20 - x 19
   29	   15	    27		ray 21.813783
   30	   11	    8		ray 21.882006
   31	   10	    21		ray 26.049134
   32	   11	    27		 y 24 - x 18
   33	   15	    22		ray 26.287415
   34	   9	    15		ray 23.891508
   35	   2	    11		ray 26.134733
