ORNL-1771 - Oak Ridge National Laboratory

0 20 40 60 80 IO0 120 140 160
I, DiSrANCE FROM SO?IRCC (cm)
Fig. 12.1. Thermal-Neutron Flux in Sugar Solu-
tion.
12.3, respectively. Plain water curves are also
shown for comparison. The gamma-ray water curve
is higher than the normal LTSF water curve because
of ihe high-energy capture gamma ray from the
lnconel window of the tank (see preceding discus-
s ion).
Since the medium contained almost as much hy-
drogen and oxygen as does plain water and con-
tained them in the same ratio, nogeometric correction
was made in calculating the effective removal cross
section, ur. The average uT for the range of 90 to
140 cm from the source was 0.750 barn. This com-
pares with a value of 0.81 i 0.05 barn from an LTSF
measurement behind a slab of graphite that con-
tained 51.3 g/cm2 of carbon, which corresponds to
PERIOD EMDlNG SEPTEMBER 70, 7954
10-3 L 1 ............... ! .... I 1 ______.._.....
70 80 90 100 1.10 (20 430
I, DISTANCE FROM SOURCE (cm)
Fig. 12.2. Fast-Neutron Dose in Sugar Solution.
the sugar-water solution at 145 cm,
In order to observe the neutron attenuation in a
medium removed from the source, the sugar-water
solution is being placed in a 36-in.-long aluminum
tank located 48.2 cm from the source. Thermal-
neutron, fast-neutron, and gamma-ray measurements
will be made in the tank. The measurements at
the interface will indicate the difference in neutron
age between water and the sugar solution for the
more penetrating of the fission neutrons.
165