DaRveX stands for "Decay at Rest nue+Pb cross(X) section measurement".
So far there has not been good low energy nue detection target.
Lead is expected to be an excellent low energy nue target because the cross section is expected to be very large and the delayed coincidence technique can be used to reduce the backgrounds.
If decay at rest nue + Pb --> e- + xn + Bi cross section is measured, it brings new possibilities to the future neutrino experiments, such as low energy nue oscillation measurements, flavor specific measurement of the supernova explosion
nue and understanding of nue-nucleus interactions.
We are planning an experiment to measure the cross section, energy spectrum and direction of the emitted electron of
nue + Pb --> e- + xn + Bi reaction at J-PARC MLF.
The beam pulse is very narrow in time and the duty cycle is low at MLF, which help to reduce the backgrounds significantly.
In this proceedings, we will explain about conceptual idea of the experiment.