Endpoint resummation in squark decays

Abstract

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 root s = 3 TeV Compact Linear Collider (CLIC), and show the softening of distributions in the sum of energies of the first two hardest jets or in the M-C variable. 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.