Table 6.

Values of the model parameters used in the fits in Sects. 4.2 and 4.3, and the corresponding systematic variations used to determine the model uncertainty on ${\alpha }_{\mathrm{s}}(M_{\mathrm{Z}})$ in Sect. 4.3. Omitted values are due to the restriction ${\mu }_{{\text{F}}_0}<m_{\text{c}}$ imposed by the RTOPT heavy flavour number scheme used here [60–62]. In these cases, to calculate the corresponding contributions to the model uncertainty, the symmetrised variation in the opposite direction is taken

Parameter	Central value	Variation
		Down	Up
$f_{\overline{\text{s}}/\overline{\text{D}}}$	0.4	0.3	0.5
$m_{\text{c}}$ (GeV)	1.42	–	1.49
$m_{\text{b}}$ (GeV)	4.5	4.25	4.75
${\mu }_{{\text{F}}_0}^2$ (GeV${}^2$)	1.9	1.6	–
$Q_{\text{min}}^2$ (GeV${}^2$)	10	7.5	12.5