Table 7.

Mass energy-absorption coefficient ratio, air to carbon

Photon energy (MeV)	$\frac{\left(m{\mathit{\mu }}_{en}\right)\text{air}}{\left(m{\mathit{\mu }}_{en}\right)\text{c}}$
0.05	1.7415
.10	1.0847
.15	1.0199
.20	1.0069
.30	1.0014
.40	1.0000
.50	0.9998
.662	.9995
1.00	.9994
1.17	.9994
1.33	.9994