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                    Vz = /2Tz7H = "f               (2.27)


From (2.23) and (2.27), the relative energy is


               Er   E + EN - 2 IN, 3M              (2.28.)


Using (2.12), (2.26) and (2.28), the computational form of the effective resonance cross section is

                          r
               a aE) = a0 T  H(a, f, Y)            (2.29)


with the Doppler broadening function H(a,  , y,) defined as



          H(   ,  Y) = 2             e e-+
                         ¢ 0 1 + Y (a+ )


                                                   (2.30)

where


          oa(E, T) = (E - E0)/kT

          (E, T) = 2V-1iTE/3M

          y(F, T) = 4kT/r2                         (2.31)


and the reduced energy variable is E = EN/kT.


        The Doppler broadened resonance absorption cross section in a plasma core reactor is given by (2.29), with H(,   , y) evaluated from tabulated values based on the resonance parameters F and E0, and the fuel temperature T.