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The NEMO Collaboration The NEMO Project
An underwater Cherenkov telescope in the Mediterranean Sea Looking for high energy neutrinos
The NEMO Collaboration
An AGN is as luminous as 10 billions suns
An Active Galactic Nucleus
AGNs emit radiowavesand optical radiation
Hubble Space Telescope can seen deeper than other Telescopes..but only neutrinos can
reveal us the sectretsof the “engine” of the AGN: the Black Hole
Buco nero ?
The brightest and most powerful sources in the Universe
The NEMO Collaboration
Neutrinos can travel the entire Universe
Electromagnetic radiation is strongly absorbed
Protons are deflected or absorbed during their journey in the space
1 parsec (pc) ∼ 3 light years ∼ 30.000 billions km
Only neutrinos may come from the deepest space
AGN and Gamma Ray Bursts are
extremely powerful sources of radiation
and particles
The NEMO Collaboration
How we see neutrinos ? In the Sea !
neutrino
The telescope will be equiopped with 4000 light detectors
neutrino
Depth: 3500m
AGN
Connection to shore: 80 km
Picture from ANATRES
The NEMO Collaboration
The Present Projects
Southern Hemisphere: AMANDA-ICECUBE
Northern Hemisphere: The Mediterranean km3
The NEMO Collaboration
The NEMO Collaboration
INFN:Bari, Bologna, Cagliari, Catania, Genova, LNF, LNS, Messina, Roma
CNR: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
The NEMO Collaboration
Investigated sites
Test Site
35° 50’ N, 16° 10’ E (3350m) in the Jonian Sea (Capo Passero) 39° 05’ N, 13° 20’ E (3400m) in the Tyrrhenian Sea (Ustica))39° 05’ N, 14° 20’ E (3400m) in the Tyrrhenian Sea (Alicudi)40° 40’ N, 12° 45’ E (3500m) in the Tyrrhenian Sea (Ponza)
The NEMO Collaboration
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 km2
• 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
The NEMO Collaboration
Vessels for marine investigation
The Oceanographic Vessel “Urania”
SOPROMAR-CNR
The Corvette “Urania”
Marina Militare ItalianaThe Oceanographic Vessel “Thetis”
SOPROMAR-CNR
The NEMO Collaboration
Current metres
Buoy
RCM8
40cm
360m
RCM8
100m
Acoustic Release
Current Metre Aanderaa RCM8
Current metre and sediment trap chain moored in Capo Passero
The NEMO Collaboration
Deep Sea Current Measurements (August 1998 - running)
Detailed report available at OGS
North10 cm/secTidal Effect Filtered out
Raw DataNorth10 cm/sec
Lat:36°30’N Long:15°50’E Depth: 3350m
current meter moored @ -3325m
Average current intensity: 3.6 cm/sec
RMS: 2.5 cm/sec
Average angle: 8° NW
The NEMO Collaboration
Sediment Trap
50 cmThe Jonian Sea has a low biological activity
Current metre and sediment trap chain moored in Capo Passero KM4
Buoy
RCM8
360m
Sediment Trap
16m
RCM8
100m
Acoustic Release trap moored @ -3210m
Collected data are integrated over a 15 days period.
Sediment Trap re-deployed in August 2001, running
The NEMO Collaboration
Biofouling short term measurement
22/12/99
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
0 5 10 15 20 25 30 35 40
days
tran
spar
ency
theta 75° theta 60° theta 45° theta 30° theta 15° theta 5°
Negligible effect of fouling after 40 days
Transparency =(PD/reference)t / (PD/reference)day#1
The NEMO Collaboration
Optical Background data
PMT: 2’’ EMI
Thershold: .16 p.e.
PMT noise: 50 Hz
Measured Rate: ~300÷350 HzCompatible with expected rate from 40K only
Capo Passero (March 2000)
The NEMO Collaboration
Capo Passero
100 km
KM2
KM3
KM4
• KM2 36°10’ N 16°19’E, depth 3350m(1: Jan ‘99)
• KM3 36°30’ N 15°50’E, depth 3345m(1: Feb ‘99, 1: Aug’99, 2: Dec ‘99)
• KM4 36°19’N, 16°04’E, depth 3341m (2: Dec ‘99, 2: March ’00, contiuing )
The NEMO Collaboration
DEep WAter Scatteringmetre
60 cm
In situ measurementof the volume scattering function
The NEMO Collaboration
Coordinated Feasibility Study for a km3 detector
Cable construction and deployment
NEXANS, Pirelli
Detector:deployment and recovery
ENI Consortium
Data/power transmission system
ALCATEL, Pirelli
UnderwaterconnectionsOcean Design
Detector:design and construction
ENI Consortium
ROV/AUVoperations
ENI Consortium
ENI Consortium: SAIPEM, SASP ENG., TECNOMARE INDUSTRIALE/SONSUB Artist’s view
The NEMO Collaboration
The telescope proposed by NEMOOPNEMO:fast montecarlo code is designed to study the telescopeperformance as a function of:
detector geometryPMT dimensions, TTSwater optical properties
Simulations show that a detector of:
4096 Optical Modules64 Towers600m height200m distance between towers75m La (Capo Passero)
May acheive:>2km2 trigger area<0.3° angular resolution (median angle)
The NEMO Collaboration
The layout of the telescope
4096 Optical Modules64 vertical structures (towers)200m distance between towers1 main Junction box1 main panel8 secondary junction boxes
(each serves 8 towers)
main JB
secondary JB
safety loop
E.O. cable from shore(100km)base of the tower
The NEMO Collaboration
Deployment of the Telescope
main JB
secondary JB
safety loop
SASP and SOSUB (ENI)propose the use of the ROV class Innovator to operate undewater connections.
Depyment sequence:main E.O. cablemain panel and main JBsecondary JBs and connections8 towers and connections ... E.O. cable from shore
(100km)
The NEMO Collaboration
Cable Design
AC solution
NEXANS in collaboration with INFNproposes the following solution:
• 100 km Electro-optical cable• double armour• 48 optical fibers• 3 or 4 electrical conductors
48 OF
conductors
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
The NEMO Collaboration
The NEMO tower
tensioning cables (dynema)
arm (fiberglass)
electronics box
Optical Modules
The tower designed by NEMO is a flexible structure tobe constructed in composite material: fiberglass and dynema
64OM per tower
4OM per arm (downward and upward directed)
40 mdistance between arms
20 marm length
150 mdistance between the seabed and lowest arm
16number of arms
600 mdistance between the lowest and the higest arm
750 mtower height
The NEMO Collaboration
The data transmission system
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,
digital signals from 4 OM (one arm) are grouped into one S1.1 electro optical converter
ALCATEL Italia in collaboration with INFNproposes a commercial, high speed
telecommunication system.The system provides:
• high reliability and MTBF• use of standard telecommunication protocols• high speed (40 Gbps per line)• auto re-configuration in case of failure
The NEMO Collaboration
Data transmission rate
1 arm (4 OM)S1.1 + STM1155 Mbps
8 Junction Boxes, 8 modules 1686 WM:4 for data transmission, 4 for redundancy16 λ each (DWDM)
48 fibers:16 for the 1686WM (2 fibers each)32 fibers for redundancy
E.O. cable
1 tower (64 OM)STM16 + 1660 SM2.5 Gbps in one λ (DWDM)
(total redundancy)
16 towers (4096 OM)1686 WM40 Gbps in 16 λ (DWDM)
(total redundancy) Shore station
The NEMO Collaboration
Data transmission in DWDM technology1686 WM 1686 WM
NEMO
Spare
1660 SM100 km
Main
Shorestation1686 WM 1686 WM
data packing (underwater):
4096 OM (electric) custom board1024 arm (optical) S1.1+ STM164 tower (optical) 1660 SM + STM164 J Box (DWDM) 1686 WM
data unpacking (shore laboratory):
4 1686 WM64 1660 SM + STM16 1024 S1.1+ STM1 4096 OM signals to be acquired
The shore station is equipped with theNetwork Managment System for the data stream control
No data compressionTrigger on shore
The NEMO Collaboration
Test Site Lab at port of Catania
Deep sea (2000 m) test for:• electronics• connectors• optical modules, acoustic modules• deployment and recovery procedures
From lab to Test site28 km optical fibres
On-shoreLab
Geostar (INGV):Oceanographic and environmental survey.
Permanent on-line seismic monitoring connected to POSEIDON network.
GEOSTAR
NEMO test
The NEMO Collaboration
The underwater cable at the NEMO test site
Junction Box
Frame for underwater connectors
Tower
5 km E.O. cable
20 km electro-optical cable:10 optical fibers6 electrical conductors
2150 m depthGEOSTAR
2050 m depth
NEMO
E.O. Cable details:
NEMO:6 fibers4 electrical conductors
GEOSTAR:4 fibers2 electrical conductors
The NEMO Collaboration
Advanced R&D programme at the Test Site
Main Frame
SecondaryJunction Boxes
NEMO Tower
PrimaryJunction Box
E.O. Cable from shore
The NEMO Collaboration
Underwater multidisciplinary laboratory
TestSite
NEMO-Site
POSEIDON - GEOSTARSubmarine seismic survey station
CREEP (UCL)Long term rock fracture analysis