KNOX
my
°
JANGLE U
JANGLE S
TEAPOT
ESS
ASYMPTOTE FOR
FLAS
T Tyr tt
z~0
TTT
107!
|
DANNY BOY
TTT
F, CURVE FOR 1 KT
|
|
NEPTUNE
titel
PRELIMINARY EMPIRICAL
Fe 107?
TTT
DYNAMIC VENTING
I
BLANCA
107"
Lt iil
ASYMPTOTE FOR NO
1073
gost
| Ld iiit
TTT
a
Ett
334
Lt
10°
10!
z/w'/3, eT/KT!/3
10?
103
Fig. 1—Fraction of gamma activity appearing in the close-in fallout
pattern.
asymptote of F, = 0.50 for z = 0, suggested by the Jangle S data in Table
1 and supported by previous work,‘ and (2) an asymptote of no dynamic
venting for z/W* = 330 ft/kt®, supported by experimental evidence® and
by studies of containment physics.°®
It should be noted that the value of F, (estimated by pattern inte-
gration) for the Sedan shot departs considerably from the curve fitted
to the whole sample of F, data. This departure could arise because of
an F, yield dependency that is inadequately known at this time. In the
absence of knowledge of such a dependency, F, estimates made from
the curve in Fig. 1 for high-yield cratering events (of the order of 100
kt and above) should be considered as uncertain by a factor of 2. It
should be further stated that F, estimates derived from Fig. 1 are
made
with the tacit assumption that the nuclear explosive is fully
tamped
and that no additives for fission-product gamma-radiation
suppression have been placed around the explosive.
It should also be mentioned that the maximum value of F, (0.75 at
z/W™® * 30) occurs at very nearly the same value of z/W" as the maxi-
mum base-surge radius (crosswind) in a neutral atmosphere, reported