a
.
a
α
=
α
emission :
.
88
R
a
236
→
.
.
86
R
n
232
+
.
2
H
e
4
(
α
−
P
a
r
t
i
c
l
e
)
.
b
.
b
β
−
β
emission :
.
88
R
a
238
→
.
.
89
A
c
228
+
(
β
−
Particl e
)
.
.
−
1
e
0
)
.
c
.
c
In some nuclides, the nucleus may capture an electron from the
K
−
K
shell . The vacancy created is filled by electrons from higher levels giving rise to characteristic
X
−
X
rays. This process is known as
K
−
K
capture . An example of
K
−
K
capture is
.
56
B
a
133
+
e
−
→
.
.
55
C
s
1333
+
X
−
.
ray
The change in the nucleus is represented by
p
+
+
e
−
→
n
p
. The neutron produced remains in the nucleus and the atomic number decreases by one unit as a result of
K
−
K
capture.
