  In the standard model of the elementary particles, the number of neutrino
flavor is three. However, there have been indications of existence of 4th
neutrino, called sterile neutrino, in some neutrino oscillation related
experiments. A number of experiments are planned to test whether such
indications are true or not. Among them, experiments which use neutrinos from
pi+, K+, mu+ decay at rest (DAR) are promising because the energy spectra of
neutrinos are very well known and clean oscillation measurements are possible.
In this proceedings, properties of such DAR neutrinos and LSND, JSNS2, OscSNS
and KPipe experiments are briefly introduced.
