Atomic and nuclear properties of tissue-equivalent gas (Methane based)
QuantityValueUnits ValueUnits
<Z/A> 0.54993     
Specific gravity (20° C, 1 atm) 1.064E-03 g cm-3   
Mean excitation energy 61.2 eV   
Minimum ionization 2.062 MeV g-1cm2 2.194E-03 MeV cm-1
Nuclear collision length 57.8 g cm-2 5.435E+04 cm
Nuclear interaction length 82.1 g cm-2 7.717E+04 cm
Pion collision length 85.3 g cm-2 8.019E+04 cm
Pion interaction length 114.1 g cm-2 1.072E+05 cm
Radiation length 39.83 g cm-2 3.743E+04 cm
Critical energy 107.61 MeV (for e-) 105.29 MeV (for e+)
Molière radius 7.85 g cm-2 7376. cm
Plasma energy ℏωp 0.70 eV   
Muon critical energy 1320. GeV   
Composition:
Elem ZAtomic frac* Mass frac
H
1
1.00
0.101869
C
6
0.38
0.456179
N
7
0.02
0.035172
O
8
0.25
0.406780
* calculated from mass fraction data

For muons, dE/dx = a(E) + b(E) E. Tables of b(E): PDF TEXT
Table of muon dE/dx and Range: PDF TEXT
Explanation of some entries