= Standard Model one-loop gauge coefficients
{c}
{title2=$(b_Y,b_2,b_3)=(41/6,-19/6,-7)$}
For three <quark generations>, their corresponding <leptons>, and one complex <Higgs doublet>, use $Q=T_3+Y$ and $D_\mu\supset ig_Y YB_\mu$. In $\mu\,dg_i/d\mu=b_i g_i^3/(16\pi^2)$ the coefficients are the displayed values. Per generation, the fermionic <Dynkin index> sums are two for both non-Abelian factors and the sum of squared hypercharges is $10/3$. The Higgs index for $SU(2)$ and its sum of squared hypercharges are each $1/2$. Gauge terms are $-22/3,-11$ for $SU(2),SU(3)$, respectively. For the grand-unified normalization $g_1=\sqrt{5/3}\,g_Y$, the Abelian coefficient instead is $41/10$.
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