INFNBari, Bologna, Catania, Genova, LNF, LNS, Napoli, Pisa, RomaUniversitàBari, Bologna, Catania, Genova, Napoli, Pisa, Roma “La Sapienza”

CNRIstituto di Oceanografia Fisica, La SpeziaIstituto di Biologia del Mare, VeneziaIstituto Sperimentale Talassografico, Messina

Istituto Nazionale di Geofisica e Vulcanologia (INGV)

Istituto Nazionale di Oceanografia e Geofisica Sperimentale (OGS)

Istituto Superiore delle Comunicazioni e delle Tecnologie dell’Informazione (ISCTI)

More than 70 researchers from INFN and other Italian institutes

Cherenkov photons

muon

Maurizio SpurioUniversity of Bologna and INFN

spurio@bo.infn.it

On behalf of the NEMO collaboration

The NEMO ProjectNeutrino Mediterranean Observatory

The NEMO Collaboration activities devoted to:• the search, characterization and long term monitoring of a deep sea site for the installation of the Mediterranean km3 -telescope• development and prototyping of technologies for the km3 (NEMO Phase-1 and Phase-2)• Montecarlo simulations

May 21-27, 2006La Biodola

Isola d'Elba (Italy)

Double armed cable2.3 km lengthSingle armed cable 20.6 kmbranching

unit

SN-1Sismic

Observatory

Shore stationShore station

• 2005: deployment of a seismic and environmental observatory of INGV (SN1) and ODE (Ocean noise Detection Experiment)

• 2006: Deployment and connection of a junction box and a fully instrumented four storey tower

The Tower StructureThe Tower Structure

main EO cablemain Junction Box

secondary JB

“tower”

Detector architecture:• Detector modularity. •Towers with non homogeneous distribution of sensors; Full height 750 m.• Reduced number of towers to reduce the number of underwater connections and allow operation with a ROV.• The towers are composed by a sequence of 15 m long storeys interconnected by tensioning cables.• Power and data cables are kept separated from the tensioning ones.

Optical Modules

Electronics container

The NEMO Phase-1The NEMO Phase-1

Junction Box = Fibreglass container +

Pressure vessels

OM = Hamamatsu 10"  R7081 SEL

Front End Module (FEM) = 200 MHz , 8bit ADC (log compression).

NEMO Phase-1: Data NEMO Phase-1: Data Transmission and DAQ Transmission and DAQ

4 Mbps/OM FEB#0

FEB#1

FEB#2

FEB#3

Software Trigger

2nd Link: Data from offshore to onshore

• 40 km electro-optical cable. • from the off-shore FCM, to an on-shore FCM (de-multiplexing station)• Physical medium: totally passive Fiber Optics link• Use of the DWDM Dense Wavelength Division Multiplexing (frequency division in the optical domain) is a completely passive optical network used for the TCM.• System assessed by the Italian Ministry of Telecommunications • Existing Stardardized TLC Self-Synchronous Serial Protocol • Data rate up to 400 Mbps

South branchCable 5 km

NEMO Phase-2: The Capo Passero NEMO Phase-2: The Capo Passero SiteSite

• Optimal site location (flat seabed, far from the shelf break and rivers). • Regular and low-value (2-3 cm/s) sea currents. • Low sedimentation rate (50 mg m-2 day-1 )

1st

FEM#2FEM#3

FEM#0FEM#1

INFN LNS

Capo Passero

OBJECTIVES:• Realization of an underwater

infrastructure at 3500 m on the Capo Passero site.

• Test of the detector structure installation procedures at 3500 m

• Installation of a 16 storey tower• Long term monitoring of the siteINFRASTRUCTURE UNDER

CONSTRUCTION• Shore station in Portopalo di Capo

Passero• 100 km electro optical cable• Underwater infrastructuresSTATUS• Purchase of the electro-optical cable

(>50 kW) under way• A building (1000 m2) located inside

the harbor area of Portopalo has been acquired. It will be renovated to host the shore station

• Project completion planned in 2007

(Left scale) Optical background rate and (Right scale) percentage of dead time (on a 10” PMT) in the Capo Passero site (3000 m) vs. time.

Decay of radioactive elements (mainly 40K) stable frequency noise (≈30 kHz on a 10” PMT at 0.3 p.e.)Light produced by biological entities (bioluminescence) random bursts with very high counting rate

The NEMO Phase-2 100 km electro-optical cable.• Voltage= 10 kV• Power > 50 kW

CONCLUSIONS Site choiceThe site offshore Capo Passero shows optimal characteristics for a km3 -telescope

Proof of the technical and budgetary feasibility of a km3 -telescope

Validation of the proposed techologies for the km3Realization of Phase-1 (2006) and Phase-2 (2007) projects. Realization of shore and deep sea infrastructures at Capo Passero

Future developmentsR&D in the KM3NeT Design Study… towards the realization of a km3 . detector

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FCM

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.Mini Tower (4storeys)

• Realization of a subsystem of the km3 including all key elements of the detector

• Project funded by INFN and MIUR

• Shore and deep sea infrastructures at 2000 m.w.e. ready

1st Link: from each Optical Module (OM) of a storey to a Floor Control Module, FCM (x4) 2 MByte/s

DEM

UX

One single optical fiber backbone per

tower

Floor 3Floor 2Floor 1

Floor 0

ADDADD

ADD

FCM3

FCM2

FCM 1

FCM0

One floor data is received on-shore by a twin FCM board, plugged on a host machine (FCM Interface)

DWDM: From offshore to onshore

On-Shore DWDM Transceivers

On-Shore Demux stage

3d link- At the FCMI, data are made available on memory buffers (Front End Buffers, or FEBs). Each FEB contains formatted data issued from the corresponding Front End Module