Construction and deployment issues for a km3 underwater detector: The NEMO experience

The NEMO collaboration aims at performing R&D towards the realization and installation of a km3 neutrino detector in deep-seawaters. One of the main problems faced for its realization is represented by the deployment, maintenance and recovery of the detector structures supporting the sensors. We have developed a new concept of detector structure, call tower, which relies on a simple but efficient unfurling system. The technique has been tested, both in air and in seawater, and will be finally validated with the realization of a prototype tower for the NEMO Phase 1 project. Results of computer simulations to study the dynamical behavior of the tower are also reported.