Theory of the Fireball

Most of the radiation comes from a tnickness of one optical mean
free patn near the radius at which ( 3.21) is satisfied. Let J be the
radiation emitted per unit area per second (which w ill be of the order
of the black body radiation; see below and Sec. 4c) ; tnen the loss of
enthalpy due to radiation, per gram per second, will be
J
- = .ep
Adizbatic expansion,
(%)adi -
As long as tne shock
tne ambient pressure
according to ( 3.11), will give an entnalpy change
is strong, i.e.,
pl, the pressure
as long as p is large compared to
behaves as
vhere t is the time from the explosion; therbfore,
1.2 p
,.- @)adi - p t
Tine rzdia-tion will be a relatively smail perturbat ion as long as
( j. 2h.) -is smaller Clan (3.27) . This wil stop be% the case when
J P
= 1.2 ,c
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