  Neutrons, originating cosmogenically or from radioactive decays, can produce
signals in dark matter detectors that are indistinguishable from Weakly
Interacting Massive Particles (WIMPs). To combat this background for the
SuperCDMS SNOLAB experiment, we are investigating designs for an active neutron
veto within the constrained space of the compact SuperCDMS passive shielding.
The current design employs an organic liquid scintillator mixed with an agent
to enhance thermal neutron captures, with the scintillation light collected
using wavelength-shifting fibers and read out by silicon photo-multipliers. We
will describe the proposed veto and its predicted efficiency in detail and give
some recent results from our R&D and prototyping efforts.
