Atomic and nuclear properties of astatine (At)
QuantityValueUnits
Atomic number 85  
Atomic mass [209.98715(6)] g mole-1
Specific gravity ?? g cm-3
Mean excitation energy 825.0 eV
Minimum ionization 1.160 MeV g-1cm2
Nuclear collision length 114.5 g cm-2
Nuclear interaction length 200.5 g cm-2
Pion collision length 137.7 g cm-2
Pion interaction length 227.0 g cm-2
Radiation length 6.07 g cm-2
Critical energy 7.60 MeV (for e-)
Molière radius 16.93 g cm-2
Plasma energy ωp 41.00 eV
Muon critical energy 141. GeV
Melting point 575.2 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 are no stable isotopes, [atomic mass] is that of the longest-lived isotope (8.1 hr).
Note: Density 5.0 g/cm3 assumed.
Table of isotopes Warning: may not be current
x ray mass attenuation coefficients