Atomic and nuclear properties of materials:
Berkelium (Bk)

Quantity	Value	Units
Atomic number	97
Atomic mass	[247.07031(4)]	g mole-1
Density	??	g cm-3
Mean excitation energy	952.0	eV
Minimum ionization	1.106	MeV g-1cm2
Nuclear collision length	119.9	g cm-2
Nuclear interaction length	211.6	g cm-2
Pion collision length	142.7	g cm-2
Pion interaction length	237.8	g cm-2
Radiation length	5.69	g cm-2
Critical energy	6.59	MeV (for e-)
Molière radius	18.32	g cm-2
Plasma energy	67.56	eV
Muon critical energy	125.	GeV
Melting point	1269.	K

For muons, dE/dx = a(E) + b(E) E. Tables of b(E): PS PDF TEXT
Table of muon dE/dx and Range: PS PDF TEXT
Explanation of some entries
Note: Since there is no stable isotope, [atomic mass] is that of the longest-lived known isotope as of Jan 2007.
Table of isotopes Warning: may not be current