APPENDIX 1
nergy Absorptio;
CALCULATION OF IONIZATION CHAMBER RESPONSE
ftormly
es
Gamma Ray Response
kt
_-576_
Wair
= ea
)
Ceo (=) (me) ve (ur/hr)
.
G.6 x
10719
amperes
10n pair
(F
x G)
.
1on pairs
am Te}
[Lr
r
‘
E
rv
where
V = active volume of chamber
P = filling pressure
(5.58 x 102 em),
(59.2 atmospheres at stp.),
F = effective attenuation due to wall
of text),
(.90,
see pg.
G = enhancement due to steel-argon boundary
(1.01),
24
be/o)da
= the average ratio of mass energy absorption
e/°)air
coefficients over the range 0.3 - 2.5 MeV (.91),
and
a/aiy) = the ratio of gas densities
and W, = 26.4).
(1.38), Wai; = 33.8
Then
k, = (.91) (1. 38)(333.8)
3-8 (5, 58x10) (59. 2) (.576) (1. 6x10719)
ul
(.90) (1.01)
4.45 x 10-14 amperes/ (ur/hr).
The estimated uncertainty in this calculated value is 5-10%.
Cosmic Ray Response
ko = RVP
.576(ion pairs/em?-sec)
ur/hr
1.6 x 10719 amperes (F x G)
ion pairs
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