ALFENDIX&
Assune:

a.
b.

FPotnt source
O.5 Mev averege beta energy

.

w 1) ear?/gm

Rate af decay follows grt?

The dose del! vered at the surface of an {raginary sphere at distance

R from a point source.

(2) x(n) =e? a
gran
where

XK(R) = dose delivured at the surface of an
imaginary wphere at distance F

x
C
ps

|
Substituting ys° se

Thens

average energy of beta particles

total mumber of disintegrations
mass absorption coefficient

v
(2) E£(R) = 0.37 re— Me
dis(atagret
goe

or

RX

—

(3.0.)

6.85
,
K(R) = OB x 107° 2
or

6.35

ailiirezs

ble ntegrat ion

-

(3.b.) K(k) Spee xo grF
RK

di«interration

Equation (3.a.) i» plotted an the at-ached graph.

{

FCR FISSICN PRCOUCT:,

f°

(5) dem 4,

pT

-

_

7

-

~1.2

where:

4

4, = disintegrations per imit tine at time "a" after detozrat'

4, @ disintegrations per unit tine at one unit of tire after
detoustion

oo

®rossi, HH, anid yltis, RN. "Dietritute’ Heba “ourves in Uniformly

4s

Pa

Fedia"

Rucjeogie:

Jule 1750, ¥. 7

.

Absorbing

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