Table 9.

Values of a_α, a_β, $\Delta {\mu }_{\text{st}}^{\text{St}}$ measured values for the three ST phantom materials. The errors in the last one or two significant figures were provided in the round parentheses.

Material	aα	aβ	$\Delta {\mu }_{\text{st}}^{\text{St}}$ (mm−1)
POM	6.5(2)	4.7(3)	0.048(7)
Resin	7.9(1.4)	6.8(8)	0.032(15)
Wax	7.5(6)	7.9(7)	0.014(12)
Weighted average	6.6(2)	5.4(3)	0.038(6)