Page 28 - bukuneutron

sorbtion cross-section in units of barns, where 1 barns
is equivalent with 10–22 mm2. Some materials appro-
priate for absorbing thermal neutron is given in Table
1.1. The materials shown in this table are widely used
for neutron conditioning in neutron gauge or neutron
instrument.

Table 1.1: Elements widely used for absorbing neutron
Element Absorption
cross-section (barns)
Sm 8250
Eu 4370
Gd 3900
Cd 3315
Dy 1100
B 755
Au 98
Li 71
Ag 62

As well known that, absorption of neutron is accom-
panied by the emission of gamma rays and the energy
of gamma is depending on the element.

1.6.4 Neutron activation

Captured of free neutron makes the target nuclei be-
come more heavier and entering the excited state re-

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