time				envelope	
period	arrivals departures	ray/coeff
   1	   4	    5		 y 17 - x 24
   2	   6	    8		ray 24.817426
   3	   17	    24		 y 19 - x 20
   4	   32	    26		ray 25.192009
   5	   33	    36		 y 20 - x 18
   6	   12	    15		 y 20 - x 18
   7	   10	    14		 y 18 - x 23
   8	   13	    14		 y 18 - x 20
   9	   29	    4		 y 18 - x 17
   10	   22	    5		ray 23.698662
   11	   27	    16		ray 24.357387
   12	   14	    31		ray 25.796184
   13	   20	    31		ray 23.949476
   14	   9	    12		ray 25.351954
   15	   17	    9		ray 25.406646
   16	   27	    13		 y 17 - x 19
   17	   22	    38		 y 19 - x 24
   18	   13	    22		ray 25.522155
   19	   29	    17		ray 23.492998
   20	   16	    12		 y 18 - x 20
   21	   20	    20		 y 23 - x 17
   22	   13	    11		 y 19 - x 20
   23	   19	    15		ray 25.151275
   24	   28	    25		 y 18 - x 20
   25	   22	    20		ray 23.608791
   26	   25	    15		 y 24 - x 19
   27	   19	    35		ray 26.333134
   28	   15	    17		ray 25.563886
   29	   15	    25		ray 22.652394
   30	   11	    15		 y 18 - x 25
   31	   6	    12		ray 25.052003
