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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 The NEMO Projectpeople.na.infn.it/~barbarin/MaterialeScientifico/NEMO/km3NEMO/nemo.pdfThe NEMO Collaboration The NEMO Project ... • auto re-configuration in

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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

Sediments

days

July 1st

Northern Ionian Sea(1997 data)

Flux

(mg

m-2

day-1

)

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

Bioluminescent bacteria

Bioluminescent bacteria on SWC

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

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

The NEMO Collaboration

Comparison of 3000 m sites: La

The NEMO Collaboration

Comparison of 3000 m sites: Lc

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

Deployment of the tower

The NEMO Collaboration

Deployment of the tower

75

0 m

15

m

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 NEMO test site: a facility of LNS-INFN

Catania

Port of Catania

LNS-INFN

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

The NEMO Collaboration

Acoustic Search for cetaceans

Blue Whale

03sec0

21

kHz

Pavan et al. 2000

Hydrophones array