The calculated dose of mcnp and openmc is different

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1

I used openmc and mcnp to simulate the B dose, H dose and N dose of the same position of the bnct head model.
Their source terms are the same。

The doses of B and H calculated by openmc and mcnp are basically consistent, but the calculated doses of N are inconsistent.

They calculated it as follows, taking the N-dose as an example:
openmc：

particle_filte = openmc.ParticleFilter('neutron')
filter_cell = openmc.CellFilter([
                                 cell11,cell12,cell13,cell14,cell15,cell16,cell17,cell18,cell19,cell20
                                 ])
#N 剂量计算  fGym2
tally7 = openmc.Tally()
dose_filter = openmc.EnergyFunctionFilter(
    [2.53E-02,3.60E-02,6.30E-02,1.10E-01,2.00E-01,3.60E-01,6.30E-01,1.10E+00,2.00E+00,3.60E+00,6.30E+00,1.10E+01,
     2.00E+01,3.60E+01,6.30E+01,1.10E+02,2.00E+02,3.60E+02,6.30E+02,1.10E+03,2.00E+03,3.60E+03,6.30E+03,1.10E+04,
     2.00E+04,3.60E+04,6.30E+04,8.20E+04,8.60E+04,9.00E+04,9.40E+04,9.80E+04,1.05E+05,1.15E+05,1.25E+05,1.35E+05,
     1.45E+05,1.55E+05,1.65E+05,1.75E+05,1.85E+05,1.95E+05,2.10E+05,2.30E+05,2.50E+05,2.70E+05,2.90E+05,3.10E+05,
     3.30E+05,3.50E+05,3.70E+05,3.90E+05,4.20E+05,4.60E+05,5.00E+05,5.40E+05,5.80E+05,6.20E+05,6.60E+05,7.00E+05,
     7.40E+05,7.80E+05,8.20E+05,8.60E+05,9.00E+05,9.40E+05,9.80E+05,1.05E+06,1.15E+06,1.25E+06,1.35E+06,1.45E+06,
     1.55E+06,1.65E+06,1.75E+06,1.85E+06,1.95E+06,2.10E+06,2.30E+06,2.50E+06,2.70E+06,2.90E+06,3.10E+06,3.30E+06,
     3.50E+06,3.70E+06,3.90E+06,4.20E+06,4.60E+06,5.00E+06,5.40E+06,5.80E+06,6.20E+06,6.60E+06,7.00E+06,7.40E+06,
     7.80E+06,8.20E+06,8.60E+06,9.00E+06,9.40E+06,9.80E+06,1.05E+07], 
    [7.88E-01,6.68E-01,5.04E-01,3.72E-01,2.84E-01,2.11E-01,1.60E-01,1.21E-01,8.97E-02,6.68E-02,5.05E-02,3.82E-02,
     2.84E-02,2.11E-02,1.60E-02,1.21E-02,9.11E-03,6.94E-03,5.53E-03,4.69E-03,4.42E-03,4.88E-03,6.22E-03,8.70E-03,
     1.30E-02,1.93E-02,2.77E-02,3.30E-02,3.40E-02,3.50E-02,3.60E-02,3.71E-02,3.88E-02,4.12E-02,4.35E-02,4.57E-02,
     4.79E-02,5.00E-02,5.22E-02,5.42E-02,5.62E-02,5.81E-02,6.10E-02,6.46E-02,6.80E-02,7.12E-02,7.44E-02,7.74E-02,
     8.02E-02,8.30E-02,8.57E-02,8.83E-02,1.24E-01,1.05E-01,1.73E-01,9.87E-02,9.76E-02,2.09E-01,2.69E-02,1.75E-02,
     1.47E-01,1.35E-01,1.27E-01,1.20E-01,1.11E-01,9.99E-02,1.30E-01,2.07E-01,2.03E-01,1.88E-01,4.62E-01,4.37E-01,
     2.93E-01,3.11E-01,4.83E-01,4.01E-01,3.27E-01,3.72E-01,5.09E-01,4.97E-01,6.52E-01,7.88E-01,9.98E-01,1.12E+00,
     1.42E+00,1.34E+00,1.61E+00,1.73E+00,1.41E+00,1.22E+00,9.94E-01,1.06E+00,1.22E+00,1.01E+00,1.11E+00,1.30E+00,
     1.28E+00,1.22E+00,1.12E+00,1.21E+00,1.39E+00,1.58E+00,1.84E+00],
    'log-log')
multiplier = openmc.EnergyFunctionFilter([0.0, 2e7], [RBE*C57*C99/C100, RBE*C57*C99/C100])
tally7.filters = [filter_cell, particle_filte, dose_filter, multiplier]
tally7.scores = ['flux']

mcnp：

fc44 N dose
f44:n   2  3  （4 5） （6 7） 8 （9 10）
        11  12  13  14  15  16  17  18  19 20
		21  22  23  24  25
fm34    2.56056e-11       $   2.5*0.107/1.00784*6.022e23/1.0e24*1.602e-10
#        de44            df44
c  c     Energy (Mev)     N 
2.53E-08	7.88E-01
3.60E-08	6.68E-01
。。。。

openmc and mcnp have the same kerma factor（for B、H、N）。
They have the same multiplication factor：2.56056e-11 = RBE* C57 *C99 /C100
May I ask why this is？

2

I calculated that the neutron flux and energy spectrum at the same location are basically the same。
Such as，the neutron flux and energy spectrum of cell11：

image
image1078×685 15.7 KB

Neutron flux：
image
but，the N dose of the same position：
image
image523×517 10 KB

3

In the mcnp piece you have fm34 instead of fm44, that is a typo for the post I hope?
what is the energy range for f44?
Is it exactly the same as the openmc case (which seems to be 0-20MeV)