Download presentation
Presentation is loading. Please wait.
Published byHomer Lambert Modified over 9 years ago
1
2000 3000 3600 NEMO The NEMO Status Report M.Taiuti on behalf of the NEMO Collaboration Merida, Yucatan, Mexico 30th International Cosmic Ray Conference July 3 - 11, 2007
2
2000 3000 3600 NEMO 2/17 The NEMO Collaboration INFN Bari, Bologna, Catania, Genova, LNF, LNS, Napoli, Pisa, Roma ► Universities Bari, Bologna, Catania, Genova, Napoli, Pisa, Roma “La Sapienza” CNR Istituto di Oceanografia Fisica, La Spezia Istituto di Biologia del Mare, Venezia Istituto 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 80 researchers involved
3
2000 3000 3600 NEMO 3/17 A Northern Telescope for High Energy Neutrinos ► The small cross section and the expected low neutrino flux require large volume telescope ~ 1 km 3 long observation time ~ yrs ► The atmospheric muon background requires a shielding > 2000 m water equivalent ► The Mediterranean Sea provides convenient sites NEMO Capo Passero 3400 m NESTOR Pylos 4000 m ANTARES Toulon 2400 m
4
2000 3000 3600 NEMO 4/17 NEMO R&D Activity ► Site location More than 25 sea campaigns since 1998 ► NEMO-KM4 80 km off-shore 3500 m depth 80 km NEMO-KM4 Catania INFN-LNS TSN TSS
5
2000 3000 3600 NEMO 5/17 NEMO-KM4 Properties ► High water transparency Data compatible with pure salt water properties No seasonal variations ► Reduced background, mostly from 40 K decay 10” PMT thres. 0.5 p.e. noise rate ~ 30 kHz Bioluminescence almost absent ► Geologically stable
6
2000 3000 3600 NEMO 6/17 NEMO km 3 Conceptual Design
7
2000 3000 3600 NEMO 7/17 NEMO km 3 Conceptual Design ► Proposed lay-out 10 junction boxes 81 towers 5832 PMTs 140-180 m Tower Secondary JB Electro-optical cable to shore Primary JB
8
2000 3000 3600 NEMO 8/17 The Expected Performances ► Simulations show excellent angular resolution and sensitivity NEMO ► 81 towers 140 m spaced ► 5832 PMTs ICECUBE ► 80 strings 125 m spaced ► 4800 PMTs IceCube simulations from Ahrens et al. Astrop. Phys. 20 (2004) 507 NEMO search bin 0.3° IceCube search bin 1° Sensitivity to a E -2 neutrino spectrum from a pointlike source
9
2000 3000 3600 NEMO 9/17 South branch 5.000 km North branch 5.220 km The NEMO Phase-1 Activity OnDE acoustic station Operating from Jan 2005 till Dec 2006 Junction Box Tower Frame Single armored cable 20.595 km Double armored cable 2.330 km BU NEMOPhase-1 Jumpers 300m Jumper300m Geoseismic station SN-1 station (INGV) Operating since Jan 2005 NEMO Phase-1 Operating since 16 Dec 2006
10
2000 3000 3600 NEMO 10/17 The NEMO Junction Box Electro-optical splitting box Glass reinforced plastic container Marine Alum. external frame Transformer Electronics Electro-optical connectors Successfully deployed Dec. 10, 2006 ► Innovative design to decouple the corrosion and pressure resistance problems
11
2000 3000 3600 NEMO 11/17 The NEMO Prototype Tower ► 4 floors Length 15 m Vertical spacing 40 m ► 16 Optical Modules with 10” PMT ► Acoustic Positioning 2 hydrophones per floor 1 beacon on the tower base ► Environmental instrumentation 1 compass + tiltmeter in each Floor Control Module CTD (Conductivity-Temperature- Depth) probe on floor 1 C* (attenuation length meter) on floor 2 ADCP (Acoustic Doppler Profiler (including compass) on floor 4
12
2000 3000 3600 NEMO 12/17 “Folded” tower ready for transportation and deployment 4 floors The NEMO Tower ► Semi-rigid structure provides “easy” assembly, transportation and deployment ► The 4-floor prototype has been successfully deployed and is operating since Dec. 16, 2006 Successfully deployed Dec. 15, 2006 Successfully connected Dec. 16, 2006
13
2000 3000 3600 NEMO 13/17 Calibration - Preliminary Results ► Absolute positioning Long Baseline acoustic positioning system based on five Acoustic Beacons 3 autonomous beacons battery operated 1 beacon on the Junction Box (not operating) 1 beacon on the Tower base ► Time offset determination network of optical fibres to flash several OMs at one time with fast LED light pulses ≈ 1.5 ns 350 m 250 m
14
2000 3000 3600 NEMO 14/17 Preliminary Results ► Systematics over one month shows good water properties: baseline rate baseline rate burst fraction evaluated as time above 1.2xbaseline burst fraction evaluated as time above 1.2xbaseline burst fraction evaluated as time above 200 kHz burst fraction evaluated as time above 200 kHz ► The Tower can recontruct atmospheric muon tracks! January 24 2007 - Run R17 file 1 Event # 366059 13 PMT hit
15
2000 3000 3600 NEMO 15/17 The NEMO Phase-2 80 km NEMO-KM4 to NEMO-KM4 ► Infrastructures for an -3500 m underwater site Electro-optical cable (50 kW – 20 fibres) ► Deployment scheduled in summer 2007 ► Deployment of DC/DC Converter beginning 2008 Shore station in PortoPalo di Capo Passero ► Building under renovation. Completion beginning 2008 NEMO Tower ► Deployment forseen by middle 2008
16
2000 3000 3600 NEMO 16/17 Conclusions and Perspectives ► The NEMO Collaboration is working on a long-term R&D program toward a km 3 -telescope in the Mediterranean Sea An optimal candidate site has been found: NEMO-KM4 The NEMO Phase-1, aiming to validate the proposed technologies, has been successfully conducted at the Catania Test Site ► Since Jan. 2005 the geoseismic and acoustic stations are fully operative ► The Junction Box and the mini-Tower has been deployed at the end of 2006 ► Data taking is in progress The NEMO Phase-2, aiming to realize the deep sea station at NEMO-KM4, is in progress ► The deployment of the electro-optical cable is scheduled in 2007 ► The set-up of the onshore station is in progress ► The deployment of a full-size tower is foreseen in 2008
17
2000 3000 3600 NEMO 17/17 Toward the -Telescope ► EU funded the joint activity for a European-scale Design Study for a km 3 -telescope in the Mediterranean Sea KM3NeT: ANTARES-NEMO-NESTOR consortium http://www.km3net.org/ ► The experience gained will contribute to the advancement of the KM3NeT activities
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.