MCNP6 Reproduction of 40 MeV D - Li Target Experiment

[zhaozq]

TL;DR

MCNP6 Reproduction of 40 MeV D - Li Target Experiment ？

I reproduced the experiment published by M. Hagiwara et al. using MCNP6. This experiment measures the neutron emission spectra of the Li(d,xn) reaction when 40 MeV deuterons interact with thick and thin lithium targets.The lithium target in the experiment is a cylinder with a diameter of 30 mm, and the thickness of the thick target is 21.4 mm. The source used in the experiment is a 40 MeV deuteron beam with a beam current intensity of 1 μA.The experiment refers to this website: https://nds.iaea.org/exfor/servlet/X4sGetSubent?plus=1&sub=E1986.002 . However, the data I calculated always differs from the expected results by more than 100 times. What could be the reason for this? Have I made mistakes in some of the settings?

1   0    -1 #2   imp:n,D=1
2   1  -0.534  7 -8 -9   imp:n,D=1
4   0   1   imp:n,D=0
c
c

c
1    so   100
c
7    pz   0
8    pz   2.14
9    cz   1.5
c
c

c
MODE      n d
SDEF      ERG=40  PAR=31 POS=0 0 -40 EFF=1e-2
          WGT=6.242197253e+12
          AXS=0 0 1  rad=d1  ara=7.068583471
          VEC=0 0 1  DIR=1 cel=1
c
si1     0  1.5
SP1     -21 1
c
c --------------------------------------------------
m1      3006.32o  0.075
        3007.32o  0.925
        nlib=32c
c --------------------------------------------------
c
f1:n     8
*c1      110 90 60 45 30 20 15 10 0
e1       1 39i 5 49i 55
c
C f2:n     8
C *c2      110 90 60 45 30 20 15 10 0
C e2       1 39i 5 49i 55
C
f11:n     8
f12:n     8
print     20  30  32  40 50  60  126  198
LOST     1e+1  1e+1
NPS      1e+7

 

[Alex A]

Welcome to Physics Forums @zhaozq,

Please show us what the result of the program is, how you are converting that to the units in the paper and what values in the paper it is supposed to match.

The beam current looks to be lower than 1uA in the paper, but I'm not sure that solves the problem. The output of MCNP is independent of intensity and the conclusions of the paper should also be independent of intensity.