The NEMO Collaboration. The NEMO Project. An underwater Cherenkov telescope in the Mediterranean Sea Looking for high energy neutrinos

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1 The NEMO Project An underwater Cherenkov telescope in the Mediterranean Sea Looking for high energy neutrinos

2 The brightest and most powerful sources in the Universe Buco nero? An Active Galactic Nucleus AGNs emit radiowaves and optical radiation An AGN is as luminous as 10 billions suns Hubble Space Telescope can seen deeper than other Telescopes..but only neutrinos can reveal us the sectrets of the engine of the AGN: the Black Hole

3 Neutrinos can travel the entire Universe AGN and Gamma Ray Bursts are extremely powerful sources of radiation and particles Protons are deflected or absorbed during their journey in the space Electromagnetic radiation is strongly absorbed Only neutrinos may come from the deepest space 1 parsec (pc) 3 light years billions km

4 How we see neutrinos? In the Sea! The telescope will be equiopped with 4000 light detectors Depth: 3500m neutrino Connection to shore: 80 km AGN neutrino Picture from ANATRES

5 The Present Projects Northern Hemisphere: The Mediterranean km 3 Southern Hemisphere: AMANDA-ICECUBE

6 The NEMO Collaboration INFN: CNR: Bari, Bologna, Cagliari, Catania, Genova, LNF, LNS, Messina, Roma Istituto di Oceanografia Fisica (La Spezia) Istituto di Biologia del Mare (Venezia) Istituto Talassografico (Messina) Istituto GEOMARE-SUD (Napoli) Istituto Nazionale di Geofisica e Vulcanologia Istituto Nazionale di Oceanorafia e Geofisica Sperimentale (Trieste) Centro Interdisciplinare di Bioacustica e Ricerche Ambientali (Pavia) Marina Militare Italiana Saclant NATO Undersea Research Centre

7 Investigated sites Test Site N, E (3350m) in the Jonian Sea (Capo Passero) N, E (3400m) in the Tyrrhenian Sea (Ustica)) N, E (3400m) in the Tyrrhenian Sea (Alicudi) N, E (3500m) in the Tyrrhenian Sea (Ponza)

8 Capo Passero characteristics distance from the cosat ~ 80 km distance from shelf break >40 km close to ports, international airport, Labs depth > 3300 m bathimetric profile is flat over 10 km 2 average current Intensity ~ 3 cm/sec (max < 15 cm/s) light attenuation length ~ 35 m (42 m in March) light absorption length ~ 70 (100 m in March) biological activity is low measured sedimentation rate and fouling rate are low

9 Vessels for marine investigation The Oceanographic Vessel Urania SOPROMAR-CNR The Oceanographic Vessel Thetis SOPROMAR-CNR The Corvette Urania Marina Militare Italiana

10 Current metres Buoy RCM8 360m RCM8 40cm 100m Acoustic Release Current Metre Aanderaa RCM8 Current metre and sediment trap chain moored in Capo Passero

11 Deep Sea Current Measurements (August running) Detailed report available at OGS 10 cm/sec North Tidal Effect Filtered out 10 cm/sec North Raw Data Lat:36 30 N Long:15 50 E Depth: 3350m current meter -3325m Average current intensity: 3.6 cm/sec RMS: 2.5 cm/sec Average angle: 8 NW

12 Sediment Trap Current metre and sediment trap chain moored in Capo Passero KM4 Buoy 50 cm The Jonian Sea has a low biological activity RCM8 360m Sediment Trap 16m RCM8 100m Acoustic Release trap -3210m Collected data are integrated over a 15 days period. Sediment Trap re-deployed in August 2001, running

13 Sediments Flux (mg m -2 day -1 ) July 1 st Northern Ionian Sea(1997 data) days

14 Biofouling short term measurement Negligible effect of fouling after 40 days 1.10 transparency /12/99 days theta 75 theta 60 theta 45 theta 30 theta 15 theta 5 Transparency =(PD/reference) t / (PD/reference) day#1

15 Bioluminescent bacteria Bioluminescent bacteria on SWC

16 Optical Background data PMT: 2 EMI Thershol d:.16 p.e. PMT noise: 50 Hz Capo Passero (March 2000) Measured Rate: ~ Hz Compatible with expected rate from 40 K only

17 Capo Passero KM3 100 km KM4 KM2 KM N E, depth 3350m (1: Jan 99) KM N E, depth 3345m (1: Feb 99, 1: Aug 99, 2: Dec 99) KM N, E, depth 3341m (2: Dec 99, 2: March 00, contiuing )

18 The Southern Ionian Sea: KM4 Temperature Salinity c(440nm) a(440nm)

19 Comparison of 3000 m sites: L a

20 Comparison of 3000 m sites: L c

21 DEep WAter Scatteringmetre In situ measurement of the volume scattering function 60 cm

22 Coordinated Feasibility Study for a km3 detector ROV/AUV operations ENI Consortium Cable construction and deployment NEXANS, Pirelli Detector: design and construction ENI Consortium Data/power transmission system ALCATEL, Pirelli Underwater connections Ocean Design Detector: deployment and recovery ENI Consortium ENI Consortium: SAIPEM, SASP ENG., TECNOMARE INDUSTRIALE/SONSUB Artist s view

23 The telescope proposed by NEMO OPNEMO: fast montecarlo code is designed to study the telescopeperformance as a function of: detector geometry PMT dimensions, TTS water optical properties Simulations show that a detector of: 4096 Optical Modules 64 Towers 600m height 200m distance between towers 75m L a (Capo Passero) May acheive: >2km 2 trigger area <0.3 angular resolution (median angle)

24 The layout of the telescope secondary JB safety loop main JB 4096 Optical Modules 64 vertical structures (towers) 200m distance between towers 1 main Junction box 1 main panel 8 secondary junction boxes (each serves 8 towers) base of the tower E.O. cable from shore (100km)

25 Deployment of the Telescope secondary JB safety loop main JB SASP and SOSUB (ENI) propose the use of the ROV class Innovator to operate undewater connections. Depyment sequence: main E.O. cable main panel and main JB secondary JBs and connections 8 towers and connections... E.O. cable from shore (100km)

26 Cable Design AC solution NEXANS in collaboration with INFN proposes the following solution: conductors 100 km Electro-optical cable double armour 48 optical fibers 3 or 4 electrical conductors 48 OF DC solution (bipolar) The use of 3 or 4 conductors is submitted to the use of: AC (three-phases) DC monopolar (sea return) DC bipolar (cable return) 48 OF conductors

27 The NEMO tower The tower designed by NEMO is a flexible structure tobe constructed in composite material: fiberglass and dynema arm (fiberglass) tower height 750 m distance between the lowest and the higest arm 600 m number of arms distance between the seabed and lowest arm m electronics box arm length 20 m distance between arms 40 m OM per arm (downward and upward directed) OM per tower 4 64 Optical Modules tensioning cables (dynema)

28 Deployment of the tower

29 Deployment of the tower 15 m 750 m

30 The data transmission system ALCATEL Italia in collaboration with INFN proposes a commercial, high speed telecommunication system. The system provides: digital signals from 4 OM (one arm) are grouped into one S1.1 electro optical converter high reliability and MTBF use of standard telecommunication protocols high speed (40 Gbps per line) auto re-configuration in case of failure The base of the tower host the module 1660-SM equipped with: 16 STM-1 modules (one per arm) 1 STM-16 (+1 for redundancy). This module groups the 16 optical signals from 16 arms into 1 wavelength,

31 Data transmission rate 1 arm (4 OM) S1.1 + STM1 155 Mbps 8 Junction Boxes, 8 modules 1686 WM: 4 for data transmission, 4 for redundancy 16 λ each (DWDM) 1 tower (64 OM) STM SM 2.5 Gbps in one λ (DWDM) (total redundancy) 16 towers (4096 OM) 1686 WM 40 Gbps in 16 λ (DWDM) (total redundancy) 48 fibers: 16 for the 1686WM (2 fibers each) 32 fibers for redundancy Shore station E.O. cable

32 Data transmission in DWDM technology 1686 WM 1686 WM Spare 1660 SM 100 km Main NEMO 1686 WM 1686 WM Shore station data packing (underwater): 4096 OM (electric) custom board 1024 arm (optical) S1.1+ STM1 64 tower (optical) 1660 SM + STM16 4 J Box (DWDM) 1686 WM data unpacking (shore laboratory): WM SM + STM S1.1+ STM OM signals to be acquired No data compression Trigger on shore The shore station is equipped with the Network Managment System for the data stream control

33 Test Site Lab at port of Catania From lab to Test site 28 km optical fibres Deep sea (2000 m) test for: electronics connectors optical modules, acoustic modules deployment and recovery procedures On-shore Lab GEOSTAR NEMO test Geostar (INGV): Oceanographic and environmental survey. Permanent on-line seismic monitoring connected to POSEIDON network.

34 The NEMO test site: a facility of LNS-INFN Catania Port of Catania LNS-INFN

35 The underwater cable at the NEMO test site 20 km electro-optical cable: 10 optical fibers 6 electrical conductors GEOSTAR 2150 m depth 5 km E.O. cable Junction Box NEMO 2050 m depth E.O. Cable details: NEMO: 6 fibers 4 electrical conductors GEOSTAR: 4 fibers 2 electrical conductors Frame for underwater connectors Tower

36 Advanced R&D programme at the Test Site NEMO Tower Secondary Junction Boxes Main Frame Primary Junction Box E.O. Cable from shore

37 Underwater multidisciplinary laboratory CREEP (UCL) Long term rock fracture analysis POSEIDON - GEOSTAR Submarine seismic survey station Test Site NEMO-Site

38 The NEMO Collaboration Acoustic Search for cetaceans 21 khz Blue Whale 0 0 sec Hydrophones array Pavan et al