Table 2.

Comparison of the fit outcome of the differential decay width in Eq. (3.4) to the BESIII ${\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}\gamma$ spectrum [81] of the binned maximum likelihood and minimum ${\chi }^2$ strategies

Quantity	Likelihood	${\chi }^2$
$A[{\text{GeV}}^{-3}]$	17.10(35)	17.07(32)
$\beta [{\text{GeV}}^{-2}]$	0.589(53)	0.599(51)
$\gamma [{\text{GeV}}^{-4}]$	$-0.204(53)$	$-0.214(50)$
${ϵ}_{\rho \omega }\times {10}^3$	1.624(73)	1.622(55)
$M_{\omega }[\text{MeV}]$	783.07(33)	783.08(31)