def theU238_lamda
      array = Array.new(23)

      array[0] = 3.2881E+0
      array[1] = 9.3805E-01
      array[2] = 3.7073E-01
      array[3] = 1.1118E-01
      array[4] = 3.6143E-02
      array[5] = 1.3272E-02
      array[6] = 5.0133E-03
      array[7] = 1.3655E-03
      array[8] = 5.5158E-04
      array[9] = 1.7873E-04
      array[10] = 4.9032E-05
      array[11] = 1.7058E-05
      array[12] = 7.0465E-06
      array[13] = 2.3190E-06
      array[14] = 6.4480E-07
      array[15] = 1.2649E-07
      array[16] = 2.5548E-08
      array[17] = 8.4782E-09
      array[18] = 7.5130E-10
      array[19] = 2.4188E-10
      array[20] = 2.2739E-13
      array[21] = 9.0536E-14
      array[22] = 5.6098E-15

      array
    end
def theU238_lamda
      array = Array.new(23)

      array[0] = 3.2881E+0
      array[1] = 9.3805E-01
      array[2] = 3.7073E-01
      array[3] = 1.1118E-01
      array[4] = 3.6143E-02
      array[5] = 1.3272E-02
      array[6] = 5.0133E-03
      array[7] = 1.3655E-03
      array[8] = 5.5158E-04
      array[9] = 1.7873E-04
      array[10] = 4.9032E-05
      array[11] = 1.7058E-05
      array[12] = 7.0465E-06
      array[13] = 2.3190E-06
      array[14] = 6.4480E-07
      array[15] = 1.2649E-07
      array[16] = 2.5548E-08
      array[17] = 8.4782E-09
      array[18] = 7.5130E-10
      array[19] = 2.4188E-10
      array[20] = 2.2739E-13
      array[21] = 9.0536E-14
      array[22] = 5.6098E-15

      array
    end
theU238_lamda is lamda in ANS-5.1-1979 Table 9.