Theory of the Fireball

equired mean free path of visible lignt at the radiating temperature
2
(also in gm/cm ) which in turn determines T~ itself.
8
We take the initial conditions from Brode, using his ernes at a
time when the inside pressure is 4.1 bars, this being closest to p = 5
a
bars of all the curves he nas published. This corresponds to a scaled
(1-megaton) time tc = Oo32> sec. At this time, important p'hysical guan-
tit ies are as given in Table VI11 ( dimensions scaled to 1 megaton) o The
last column of the table is not given by Brode but will be explained in
Sec. 6c. In the table, we have defined a quantity proportional to the
mass,
0
J
where R is measured in hundreds of meters. It is interesting that the mass
of the warm layer is much (4.6 times) larger than that of the isothermal
sphere. Its volwne is about 2.4 tfmes larger in Brode 's calculations.
Table VIII. Conditions When Cooling Wave Reaches Isothermal
Sphere, According to Brode
Isothermal Warm Layer
Sphere Brode Sec. 6c
Outer radius, meters 38.5 517 438
Mean temperature T' 3.0 0.70
1