  We present neutrino-based options for verifying that the nuclear reactors at
North Korea's Yongbyon Nuclear Research Center are no longer operating or that
they are operating in an agreed manner, precluding weapons production. Neutrino
detectors may be a mutually agreeable complement to traditional verification
protocols because they do not require access inside reactor buildings, could be
installed collaboratively, and provide persistent and specific observations. At
Yongbyon, neutrino detectors could passively verify reactor shutdowns or
monitor power levels and plutonium contents, all from outside the reactor
buildings. The monitoring options presented here build on recent successes in
basic particle physics. Following a dedicated design study, these tools could
be deployed in as little as one year at a reasonable cost. In North Korea,
cooperative deployment of neutrino detectors could help redirect a limited
number of scientists and engineers from military applications to peaceful
technical work in an international community. Opportunities for scientific
collaboration with South Korea are especially strong. We encourage policymakers
to consider collaborative neutrino projects within a broader program of action
toward stability and security on the Korean Peninsula.
