Wa
as fission products.
ov21620
The induced products have no effect on the value
of a or ap in terms of fissions but do effect the value of I(t) in both
contour ratios and on a and ap in other units of measure such as disintegrations per unit time. For a given composition of radionuclides
deposited uniformly over an extended area of the ideal plane, the radi-
ation intensity over the plane (say, at 3 ft) is given by
I(t) = Go (t) a (t)
(4)
in which G2 (t) is e conversion coefficient for a(t) on a smooth infinite plane and whose
value depends on the units of a(t). If a(t) is in
d/s per sq ft, then G, (t) has the units r/br/(d/s per sq ft). If a(t)
is in fissions per sq ft then (2 hes the units r/br/(fise/sq ft); in the
latter units the parameter a does not depend on t.
Values of G (t) for
the fission products from several kigds pf fission have been calculated
as a function of time after fission.“’~2"
Keepin, the fission products
and induced activities (capture products) separat: allows the seperation
of G (t) into two parts so that
G2 (t) = ip(t) + 1,(t)
(5)
in which ip,(t) is the value of the (r/hr)/(fission/sq ft) for the fis-
sion products and Agp(t) in (r/br)/(fission/sq ft) for the capture pro-
ducts is given by
ete ee
ip(t) = 2, e,i,(t)
in which c,
(6)
is the number of neturon captures to form the jth radiomic-
lide per fission (radioactive atoms produced per fission) and i,(t) is
the radiation rate (r/hr) at time, t, after detonation from one‘radioactive atom (corrected to zero time) per sq ft. The total radioactivity
produced by the device is given by
8, = KoW
pOE/NY
(7)
in which W is the total nuclear yield of the device, b is the ratio of
fission to total yield and K is a constant depending on the units of am
'
a