  We review soft-collinear effective theory (SCET), and apply it to discuss
quark electromagnetic form factor, then present the resumed transverse momentum
distribution of Higgs-boson production via gluon fusion under this framework,
where we derive a relatively full differential formula in transverse momentum
$Q_T$ space like one which have been obtained by Dokshitzer-D'Yanov-Troyan
(DDT) in perturbative Quantum Chromodynamics (pQCD). Furthermore, our above
result can be generalized to even higher order. Comparing our formula with the
integral formula of Collins-Soper-Sterman (CSS) in impact parameter $b$ space,
we establish the relationship between the anomalous dimension of operator
together with matching coefficients in SCET and the well-known coefficients A,
B and C in pQCD, which also provides a relative natural and convenient method
to treat the similar questions as ones of CSS, such as the matching in
nonperturbative region. Finally, the joint resummation method in SCET is
briefly discussed.
