1. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 KM3NeT: a deep-sea neutrino telescope in the Mediterranean Sea Paolo Piattelli - INFN/LNS Catania (Italy) on behalf of the KM3NeT Consortium

2. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 What is KM3NeT ? An acronym for km3 Neutrino Telescope A future deep-sea Research Infrastructure hosting a km3 scale neutrino telescope and facilities for associate marine and earth sciences A Consortium between the groups/Institutions that have developed the pilot neutrino telescope projects in the Mediterranean Sea (Antares, Nemo, Nestor) –Two projects funded by the EU –Design Study (2006-2009): aims at developing a cost- effective design for the construction of a 1 km3 neutrino telescope –Preparatory Phase (2008-2010): preparing for the construction by defining the legal, financial ad governance issues as well as the pre-production of the telescope components

3. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Timeline towards construction

4. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 KM3NeT Conceptual Design Report Will soon be available on the KM3NeT consortium web site http://www.km3net.org Describes the scientific objectives, and the concepts behind the design, construction, and operation of the KM3NeT Research Infrastructure

5. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Science case Astroparticle physics with neutrinos –“Point sources”: Galactic and extragalactic sources of high-energy neutrinos –The diffuse neutrino flux –Neutrinos from Dark Matter annihilation Search for exotics –Magnetic monopoles –Nuclearites, strangelets, … Neutrino cross sections at high(est) energies Earth and marine sciences –long-term, continuous measurements in deep-sea –marine biology, oceanography, geology/geophysics, …

6. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Why in the Mediterranean Sea? > 25% Visibility > 75% Visibility Observed sky region in galactic coordinates assuming efficiency for downward hemisphere.

7. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Design goals Sensitivity to exceed IceCube by “substantial factor” Core process:  +N   +X at neutrino energies beyond 100 GeV Lifetime > 10 years without major maintenance, construction and deployment < 4 years Some technical specifications: –time resolution 2 ns –position of OMs to better than 40 cm accuracy –two-hit separation < 25 ns –false coincidences dominated by marine background –coincidence acceptance > 50% –PM dark rate < 20% of 40 K rate

8. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Reference detector Sensitivity studies with a common detector layout Geometry: –15 x 15 vertical detection units on rectangular grid, horizontal distances 95 m –each carries 37 OMs, vertical distances 15.5 m –each OM with 21 3’’ PMTs NOT the final KM3NeT design! Effective area of reference detector

9. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Point source sensitivity Based on muon detection Factor ~3 more sensitive than IceCube –larger photo- cathode area –better direction resolution Study still needs refinements

10. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Diffuse fluxes Assuming E -2 neutrino energy spectrum Only muons studied Energy reconstruction not yet included

11. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Configuration studies Various geometries and OM configurations have been studied None is optimal for all energies and directions Local coincidence requirement poses important constraints

12. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 KM3NeT CDR contents 1.Introduction 2.Science case 3.The KM3NeT concept 4.Neutrino telescope design goals 5.Pilot projects 6.Site investigations 7.Technical implementation 8.Development plan 9.Project implementation 7.1.Optical modules 7.2.Information technology 7.3.Mechanics 7.4.Deep-sea and shore infrastructures 7.5.Deployment 7.6.Calibration

13. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Optical Modules Standard or directional … Segmentation of photo cathode of 10” PMT

14. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Optical Modules … or many small PMTs … Basic idea: Use up to 30 small (3’’ or 3.5’’) PMTs in standard sphere Advantages: –increased photocathode area –improved 1-vs-2 photo electron separation  better sensitivity to coincidences –directionality Prototype arrangements under study

15. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Optical Modules … or hybrid solutions … Idea: Use high voltage (~20kV) and send photo electrons on scintillator; detect scintillator light with small standard PMT. Advantages: –Very good photo-electron counting –large angular sensitivity possible Prototype development in CERN/Photonis/CPPM collaboration Quasar 370 (Baikal)

16. Paolo Piattelli - KM3NeTIAPS - Golden, 6-8 may 2008 Mechanical structures -Extended tower structure: NESTOR like, arm length up to 60 m -Flexible tower structure: NEMO like, tower deployed in compactified “package” and unfurls thereafter Four options considered -String structure: Compactified at deployment, unfolding on sea bed -Cable based concept: one (large) OM per storey, separate mechanical and electro- optical function of cable, compactified deployment Tower like String like