KM3NeT a Deep Sea Challenge for neutrino astronomy

1. KM3NeT a Deep Sea Challenge for neutrino astronomy Ciro Bigongiari Representing the KM3NeT consortium UNWAT - 2007

2. What is KM3NeT ? • A next generation neutrino telescope • A future research facility for deep sea sciences • A Consortium of 40 institutes from 10 European countries. • An EC Design Study for a neutrino telescope in the Mediterranean sea UNWAT - Valencia

3. The KM3NeT Consortium … • Cyprus: Univ. Cyprus Nicosia • France: CEA/Saclay, CNRS/IN2P3 (APC Paris, CPP Marseille, IReS Strasbourg), Univ. Haute Alsace/GRPHE, IFREMER • Germany: Univ. Erlangen,FTZ (Univ. Kiel) • Greece: HCMR Anavissos, HOU Patras, NCSR Athens, NOA/Nestor Athens, Univ. Athens • Ireland: DIAS Dublin • Italy: CNR/ISMAR,INFN (Univs. Bari, Bologna, Catania, Genova, Napoli, Pisa, Roma-1, LNS Catania, LNF Frascati), INGV,TecnomareSpA • Netherlands: NIKHEF/FOM Amsterdam, Univ. Amsterdam, Univ. Utrecht, KVI ( Univ. Groningen) • RomaniaISS Bucharest • Spain: IFIC (CSIC) Valencia, Univ. Valencia, UP Valencia • UK: Oceanlab (Univ. Aberdeen), Univ. Leeds, Univ. Liverpool, Univ. Sheffield • Particle/Astroparticle institutes (32)–Sea science/technology institutes (7) –Coordinator UNWAT - Valencia

4. KM3NeT Design Study • Design Study supported by the European Union with 9 M€, overall budget ~20 M€. • Started on Feb. 1, 2006; will run for 3 years. Objectives • Design a cost effective neutrino telescope with : • Effective volume > 1 Km3 • Angular resolution for muons (for neutrino energy > 10 TeV) 0.1° • Energy threshold : few 100 GeV. When pointing ~100 GeV • Sensitivity to all neutrino flavors, CC/NC reactions • Field of view, close to 4πforhighenergies Deliverables • Conceptual Design Report by Fall 2007 • Technical Design Report by the end of 2008 UNWAT - Valencia

5. The Physics Case Supernova Remnants ? Dark Matter ? ? Pulsar Wind Nebula ? ? ? ? ? ? ? Many astrophysical objects can be sources of neutrinos Micro Quasars Active Galactic Nucl. Gamma-Ray Burts UNWAT - Valencia

6. Why in the Mediterranean ? Many candidate sources visible only from the northern hemisphere Observed sky region in galactic coordinates assuming efficiency for downwardhemisphere. > 75% Visibility > 25% Visibility UNWAT - Valencia

7. Detection Principle Undersea Neutrino Telescope p  Earth   p Neutrino source UNWAT - Valencia

8. Possible Sites – Pilot Projects Site choice will depend on: • Depth • Distance from shore • Bioluminescence rate • Sedimentation • Biofouling • Sea currents • Earth quake profile • Access to on-shore facilities Three Pilot Projects are already ongoing: ANTARES NEMO NESTOR UNWAT - Valencia

9. Detector Architecture Many different geometries are under study by detailed simulations Cuboid Ring Hexagonal Clustered UNWAT - Valencia

10. Detector Cabling A Km3 detector means many detector units to be cabled. Experience teach us that wet-connections are a weak point. Possible redundant data/power cabling layout UNWAT - Valencia

11. Detector Elements KM3NeT will be composed of many identical units anchored to the sea bed. They can flexible or rigid. Rigid towers Strings Hybrid solution NESTOR NEMO ANTARES UNWAT - Valencia

12. Junction Box/Electronic vessel • Technology with double vessel system • Decouple resistance to pressure and resistance to corrosion • Redundancy of the protection system against water leakage • Cost reduction • Possibility to use not strategic material GRP & Steel instead of Titanium • Use of the electronic under pressure Steel vessel resistant to pressure GRP vessel resistant to corrosion Filled with oil to transfer pressure to the inner steel vessel UNWAT - Valencia

13. Segmentation of photo cathode of 10” PMT Multi PMTs in one glass sphere Optical Modules Minimize the number of connectors per photocathode area: Smart tube X-HPD UNWAT - Valencia

14. Deployment Technique The deployment of a 1 Km3 requires a fast and cost-effective technique Unfurled detector units Furled detector unit before the deployment Many detector units can be deployed in one mission saving time and money UNWAT - Valencia

15. Associated Sciences The infrastructure of the KM3NeT neutrino telescope will serve as a platform for instrumentation for ocean sciences: Oceanology Marine Biology Environmental Science Geology and Geophysics These sciences include measurements of the deep sea environment, including water purity, undersea current, bioluminescence monitoring, biosedimentation studies and sea floor studies and sea floor seismometry. • KM3NeT site in • ESONET (European Sea-floor Observatory NETwork): strategic long term monitoring capability in geophysics, geo-technics, chemistry, biochemistry, oceanography, biology and fisheries. • EMSO (European Multi-disciplinary Sea-floor Observatory research infrastructure): management and conservation of marine resources, geo-hazards and climate change in the deep-sea UNWAT - Valencia

16. Foreseen temporal outline Design Study Preparatory Phase Construction Jan 2008 Mid 2010 Feb 2006 Assembly model Tenders CDR TDR Financial plan Now UNWAT - Valencia

17. Conclusions and Outlook • The Mediterranean-Sea neutrino telescope projects ANTARES, NEMO and NESTOR have proven the feasibility of large-scale deep-sea neutrino telescopes. • The EU-funded KM3NeT Design Study (2006-09) is well on its way • Building on experience of ongoing neutrino telescope projects • Many technological innovations needed • New ideas developed • CDR workshop in November 2007 • FP7-Preparatory Phase proposal approved • Commitments for construction • Governance • Site selection • System prototype • Technical Design Report by the end of 2008. UNWAT - Valencia