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A new proposal to compute the anomalous chromomagnetic dipole moment of thetop quark, $\hat{\mu}_t$, in the Standard Model is presented. On the basis ofthe 5-dimensional effective Lagrangian operator that characterizes thequantum-loop induced chromodipolar vertices $gt\bar{t}$ and $ggt\bar{t}$, the$\hat{\mu}_t$ anomaly is derived via radiative correction at the 1-loop levelfrom the non-Abelian 4-body vertex function $ggt\bar{t}$. We evaluate$\hat{\mu}_t(s)$ as a function of the energy scale $s=\pm E^2$, for$E=[10,1000]$ GeV, taking into account the running of the quark masses andalpha strong through the $\overline{\mathrm{MS}}$ scheme. In particular, wefind that at the typical energy scale $E=m_Z$ for high-energy physics,similarly to $\alpha_s(m_Z^2)$, $\alpha(m_Z^2)$ and $s_W(m_Z^2)$, the spacelikeevaluation yields $\hat{\mu}_t(-m_Z^2)$ $=$ $-0.025$$+$$0.00384i$ and thetimelike $\hat{\mu}_t(m_Z^2)$ $=$ $-0.0318$$-$$0.0106i$. ThisRe$\thinspace\hat{\mu}_t(-m_Z^2)$ $=$ $-0.025$ from $ggt\bar{t}$ is even closerto the experimental central value $\hat{\mu}_t^\mathrm{Exp}=$ $-0.024$, thanthat coming from the known 3-body vertex function $gt\bar{t}$, $-0.0224$. Onceagain, the Im$\thinspace\hat{\mu}_t(-m_Z^2)$ part is due to the contribution ofvirtual charged currents, just like in the $gt\bar{t}$ case. We can infer thatthe spacelike prediction is the favored one.

The top quark chromomagnetic dipole moment in the SM from the 4-body vertex function