c2v,        xsec
 -2.0, 0.009058174
-1.75, 0.007624201
 -1.5, 0.006315373
-1.25, 0.005131690
 -1.0, 0.004073151
-0.75, 0.003139759
 -0.5, 0.002331510
-0.25, 0.001648407
  0.0, 0.001090449
  0.1, 0.000902306
  0.2, 0.000734186
  0.3, 0.000586090
  0.4, 0.000458017
  0.5, 0.000349967
  0.6, 0.000261940
  0.7, 0.000193936
  0.8, 0.000145956
  0.9, 0.000117999
  1.0, 0.000110065
  1.1, 0.000122154
  1.2, 0.000154266
  1.3, 0.000206402
  1.4, 0.000278561
  1.5, 0.000370742
  1.6, 0.000482948
  1.7, 0.000615176
  1.8, 0.000767427
  1.9, 0.000939702
  2.0, 0.001132000
 2.25, 0.001700347
  2.5, 0.002393838
 2.75, 0.003212473
  3.0, 0.004156254
 3.25, 0.005225181
  3.5, 0.006419252
 3.75, 0.007738467
  4.0, 0.009182829