The Double-Chooz experiment goal is to search for a non-vanishing value of
the Theta13 neutrino mixing angle. This is the last step to accomplish prior
moving towards a new era of precision measurements in the lepton sector. The
current best constraint on the third mixing angle comes from the CHOOZ reactor
neutrino experiment sin(2θ13)2<0.2 (90% C.L., Δmatm2=2.0 eV2). Double-Chooz will explore the range of
sin(2θ13)2 from 0.2 to 0.03-0.02, within three years of data
taking. The improvement of the CHOOZ result requires an increase in the
statistics, a reduction of the systematic error below one percent, and a
careful control of the backgrounds. Therefore, Double-Chooz will use two
identical detectors, one at 150 m and another at 1.05 km distance from the
Chooz nuclear cores. In addition, we will to use the near detector as a ``state
of the art'' prototype to investigate the potential of neutrinos for monitoring
the civil nuclear power plants. The plan is to start operation with two
detectors in 2008, and to reach a sensitivity sin2(2θ13) of 0.05
in 2009, and 0.03-0.02 in 2011.Comment: 3 pages, 1 figure, Proceedings of Nufact'04, July 26 - August 01
2004, Osak