Atomic and nuclear properties of fermium (Fm)
Atomic number 100  
Atomic mass [257.09510(5)] g mol-1
Density ?? g cm-3
Mean excitation energy 994.0 eV
Minimum ionization 1.090 MeV g-1cm2
Nuclear interaction length 214.4 g cm-2
Nuclear collision length 121.2 g cm-2
Pion interaction length 240.2 g cm-2
Pion collision length 144.0 g cm-2
Radiation length 5.62 g cm-2
Critical energy 6.42 MeV (for e-)
Muon critical energy 122. GeV
Molière radius 18.57 g cm-2
Plasma energy ωp 67.24 eV
Melting point 273.1 K
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: Since there is no stable isotope, [atomic mass] is that of the longest-lived isotope known as of Jun 2017.
Note: Density 14.0 g/cm3 and Ieff = 994 eV assumed in calculating critical energies and dE/dx.
Table of isotopes via WIKIPEDIA