Nestor Project

The NESTOR Project (Neutrino Extended Submarine Telescope with Oceanographic Research Project) is an international scientific collaboration whose target is the deployment of a neutrino telescope on the sea floor off Pylos, Greece.

Neutrinos are elementary particles first detected in the 1950s, long after their theoretical prediction by theorist Wolfgang Pauli. Neutrinos (or anti-neutrinos) are created during certain nuclear reactions, where protons are transformed into neutrons and vice versa. Neutrinos do not interact with matter via either the electromagnetic, the strong nuclear, or gravitational forces, since they are electrically neutral leptons and their rest mass is very small. They interact with the nucleons (neutrons and protons) only via weak nuclear interactions. Since they do not interact with matter via the electromagnetic or gravitational forces, it is extremely difficult to detect them. Since their mass is very small (less than 14 eV) they travel with speeds that are very close to the speed of light in vacuum.

Because neutrinos are very weakly interacting, neutrino detectors must be very large in order to detect a significant number of neutrinos. After completion, NESTOR will consist of a large number of glass balls (the "eyes") containing photomultiplier tubes. The "eyes" are connected with star shaped titanium frames. Many frames compose a NESTOR tower. The whole construction is placed at the bottom of the sea to reduce noise from cosmic radiation (depth 4000m). The detectors are connected with the terminal station through a 31 km long deep sea, optic fiber cable for data collection.

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