Table 2.

Two parameters related to the mass absorption coefficient η of W: (1) the experiment α relating the mass absorption coefficient and the energy via η ∝^−α below the threshold and (2) the branching ratio τ of the M₅ contribution to the M₄ contribution of the mass absorption coefficient of W. “General values” refers to averages over many elements from experiments performed in the early days of quantum mechanics. “Statistical ratio” is the ratio of the number of electrons in the 3d_5/2 and 3d_3/2 orbitals

	W		Ta
	α	τ	α	τ
Expt. [13]	2.23
Expt. [21]	2.74
Present IPA [20]	2.01	1.59	2.02	1.71
Present RTDLDA [20]	2.76	1.23	2.60	1.40
Present feff [2,3]	1.80	1.51	1.75	1.40
Expt. [15]	2.74 ± 0.81	1.30 ± 0.30
Present expt.	2.56 ± 0.25	1.26 ± 0.20	2.71 ± 0.30	1.24 ± 0.20
General values [6]	2.5–3.0		2.5–3.0
Statistical ratio		1.5		1.5