  We study soft and collinear gluon emission in squark decays to
quark--neutralino pair, at next-to-next-to-leading logarithmic (NNLL) accuracy
in the end-point region, using Soft Collinear Effective Theory (SCET), and at
next-to-leading (NLO) fixed order in the rest of the phase space. As a
phenomenological case study we discuss the impact of radiative corrections on
the simultaneous measurements of squark and neutralino masses at a linear
$e^{+}e^{-}$ collider based on $\sqrt{s} = 3$ TeV Compact Linear Collider
(CLIC). Since the majority of mass measurement techniques are based on edges in
kinematic distributions, and these change appreciably when there is additional
QCD radiation in the final state, the knowledge of higher-order QCD effects is
required for precise mass determinations.
