Page 64 - bukuneutron

in mass number will cause the element of materials
become unstable and will decay to form stable condi-
tion. Some gamma radiation with specific energy are
emitted during decay process. The energy of gamma
emited from activated sample is specific and unique for
different element. This will gives information about the
type of element contains in the material. Since the ma-
terials usually consists of several materials, therefore,
a series of gamma energy and intensity is produced.
The gamma energy spectrum emitted from the acti-
vated elements of material is detected and recorded
by gamma spectrometer.Hence, this is the important
principle of neutron activation analysis. Mass of ma-
terial is determined by the weight of the nucleus and
mass for charge is given in Table [?].

Table 3.1: Mass of Neutron, Proton and Electron.

Entity Mass Charge

Neutron 1.008665 u 1 No electrical charge

Proton 1.007277 u Positive charge

Electron 0.000548 u Negative charge

There are sequence of events occurring during nu-
clear reaction. The most common type of nuclear re-
action used for NAA is the neutron capture or (n, γ)
reaction as illustrated in Figure 3.1. The compound nu-

11u = 1.66053906660E27 kg

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