Atomic and nuclear properties of silica aerogel for rho = 0.2 (0.03 H2O, 0.97 SiO2)
QuantityValueUnits ValueUnits
<Z/A> 0.50093     
Specific gravity 0.2000 g cm-3   
Mean excitation energy 139.2 eV   
Minimum ionization 1.740 MeV g-1cm2 0.3480 MeV cm-1
Nuclear collision length 65.0 g cm-2 324.9 cm
Nuclear interaction length 97.3 g cm-2 486.7 cm
Pion collision length 91.7 g cm-2 458.6 cm
Pion interaction length 128.4 g cm-2 641.9 cm
Radiation length 27.25 g cm-2 136.2 cm
Critical energy 56.07 MeV (for e-) 54.63 MeV (for e+)
Molière radius 10.31 g cm-2 51.53 cm
Plasma energy ωp 9.12 eV   
Muon critical energy 762. GeV   
Composition:
Elem ZAtomic frac* Mass frac
O
8
2.00
0.543192
Si
14
1.00
0.453451
H
1
2.00
0.003357
* 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
Note: See A. R. Buzykaev et al, NIM A433 396 (1999)