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Astronomia a neutrini con km 3 sott’acqua e ghiaccio

Astronomia a neutrini con km 3 sott’acqua e ghiaccio. Why neutrino astronomy?. Neutrino astronomy aims at the identification of the sources of the UHECRs . Neutrinos traverse space without being deflected or attenuated They point back to their sources

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Astronomia a neutrini con km 3 sott’acqua e ghiaccio

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  1. Astronomia a neutrini con km3 sott’acqua e ghiaccio

  2. Why neutrino astronomy? Neutrino astronomy aims at the identification of the sources of the UHECRs • Neutrinos traverse space without being deflected or attenuated • They point back to their sources • They allow to view into dense environments • Neutrinos are produced in high energy hadronic processes • They can allow distinction between hadronic and leptonic acceleration mechanisms Absorption lenght of CR in the Universe

  3. Neutrino production • proton interactions • p  p (SNR,X-Ray Binaries) • p   (AGN, GRB, microQSO) • decay of pions and muons • Proton acceleration • Fermi mechanism • proton spectrum dNp/dE ~E-2 Astrophysical jet Neutrino production in cosmic accelerators Particle accelerator electrons are responsible for gamma fluxes (synchrotron, IC)

  4. HE proton interaction on ambient p or   0 HE proton Muons and muon-neutrinos   Target protons + -  Shock wave SN shells, clouds,.. Neutral pion produced in pp collisions may produce the observed TeV  fluxes (SNR RX J1713.7-3946, Aharonian 2004,2005) Beam dump in astrophysical jet environment (GRB,AGN,microQSO) HE proton muons and neutrinos Matter shells pions Target photons GRB (Waxman), AGN jets (Mannheim), microQSO (Levinson) Shock waves Beam dump in gas dense environment (SNR)

  5. atmospheric muon ~5000 PMT The observation of TeV neutrino fluxes requires km2 scale detectors Cherenkov light neutrino muon Connection to the shore depth >3000m neutrino

  6. Candidate sources and expected events Probability to produce a detectable muon (Eµ >Emin) Neutrino flux Earth transparency Diffuse fluxes GZK neutrinos 0.5 / year GRB (Waxman) 50 / year AGN (thin) (Mannheim) few / year (thick) >100 / year Point-like sources GRB (030329) (Waxman) 1-10 / burst AGN (3C279) (Dermer) few / year Galactic SNR (Crab) (Protheroe) few / year Galactic MicroQuasar (Distefano) 1-100 / year Expected events in a 1 km2 detector

  7. Status of collaborations 2400m 3800 m NEMO ANTARES NESTOR 3500m BAIKAL, AMANDA:taking data NESTOR, ANTARES, NEMO R&D:under construction ICECUBE: under construction (expected 2010) KM3NET – Meditteranean : EU Design Study 2006-2008 BAIKAL AMANDA ICECUBE

  8. Two neutrino telescopes South Pole Mediterranean Galactic Centre Crab Crab VELA SS433 GX339-4 VELA SS433 GX339-4 HESS data • In order to obtain the whole sky coverage 2 telescopes must be built • The Galactic Centre is observable only from the Northern Hemisphere

  9. HESS Sources Observable only from the Mediterranean

  10. The largest detector up to date: AMANDA AMANDA-II 19 strings 677 OMs Depth 1500-2000m Optical Module Effective Area  104 m2 (E  TeV) Angular resolution  2°

  11. Atmospheric neutrinos Atmospheric neutrinos is the background for cosmic neutrinos but in the same time an important calibration tool. Neutrinos up to a few 100 TeV have been observed in AMANDA horizontal vertical  Spectrum can be used to search for E-2 component Hulth, NOVE 2006 Limit on diffuse E-2νμflux (100-300 TeV): E2μ(E) < 2.9·10–7 GeV cm-2 s-1 sr-1

  12. Point Source SearchSelected Sources Source Nr. of  events (4 years) Expected backgr. (4 years) Flux Upper Limit F90%(En>10 GeV) [10-8cm-2s-1] Markarian 421 6 5.58 0.68 1ES1959+650 5 3.71 0.38 SS433 2 4.50 0.21 Cygnus X-3 6 5.04 0.77 Cygnus X-1 4 5.21 0.40 Crab Nebula 10 5.36 1.25 Preliminary SensitivityFn/Fg~2 for 200 days of “high-state” and spectral results from HEGRA Crab Nebula: MC probability to obtain an entry with at least this excess significance is 64% … out of 33 Sources Systematic uncertainties under investigation selected objects → no statistically significant effect observed

  13. The future of underice neutrino telescope: ICECUBE The technology for underice detectors is reliable. The next step is the construction of the km3 detector ICECUBE. IceTop air shower array 80 pairs of ice Cherenkov tanks 80 strings (60 PMT each) 4800 10” PMT (only downward looking) 125 m inter string distance 17 m spacing along a string Instrumented volume: 1 km3 (1 Gton) First string deployed Jan 2005 IceCube will be able to identify  tracks from  for E > 1011 eV cascades from e for E > 1013 eV  for E > 1015 eV February 2006 9 strings deployed

  14. 14.5 m Anchor/line socket ANTARES is installing a 0.1 km2 demonstrator detector close to Toulon to be deployed by 2005-2007 • 12 lines • 25 storeys / line • 3 PMTs / storey • 900 PMTs ANTARES 350 m ANTARES deployed Line 1 in February. 2006. 40 km to shore Junction Box 100 m ~70 m Submarine links

  15. Operation 2006-01 (1st part) line 1 deployment Waiting in Foselev hangar since 15th december…loaded on 13th feb 2006

  16. ANTARES Sea Operations

  17. Real Data: atmospheric muons reconstructed Result of Fit • Run 21240 Event 12505 • q = 101o • P(c2,ndf) = 0.88 z [m] Antares preliminary t [ns] • Run 21240 Event 12527 • q = 146o • P(c2,ndf) = 0.61 z [m] t [ns]

  18. NEMO • The NEMO Collaboration is dedicating a special effort in: • search, characterization and monitoring of a deep sea site adequate for the installation of the Mediterranean km3; • development of technologies for the km3 (technical solutions chosen by small scale demonstrators are not directly scalable to a km3).

  19. The Capo Passero deep sea site • The average depthis 3500 m, the distance from shore is 100 km. • It is located in a wide abissal plateu far from shelf breaks and geologically stable. • Optical properties of deep sea water are the best measured among investigated sites (absorption length close to optically pure water astro-ph\0603701) • Optical background is low (25 kHz on 10’’ PMT at 0.5 s.p.e. threshold) and mainly due to 40K decay since the bioluminesce activity is extremely low. • Underwater currents are very low (2.5 cm/s) and stable. After eight years of activity in seeking and monitoring abyssal sites in the Mediterranean Sea the NEMO collaborationhas chosen theCapo Passerosite. The site has been propsed to ApPEC on january 2003 ascandidate site for the installation of the km3.

  20. Seawater optical properties in Toulon and Capo Passero Optical properties have been measured in joint ANTARES-NEMO campaigns in Toulon and in Capo Passero (July-August 2002) NEMO data ANTARES data Average values 2850÷3250 m • Absorption lengths measured in Capo Passero are close to the optically pure sea water data • Differences between Toulon and Capo Passero are observed for the blue light absorption • Light Absorption and attenuation lengths measured in Capo Passero don’t show seasonal dependence

  21. Optical background in Toulon and in Capo Passero Optical data measured in Capo passero are consistent with biological data: no luminescent bacteria have been observed in Capo Passero below 2500 m 35 2.0% 30 kHz 30 1.5% Spring 2003 data Counting rate (kHz) Time above 200 kHz 25 1.0% 20 0.5% Optical background rate is much higher in Toulon. 15 0.0% 0 7 14 21 28 35 42 49 Days

  22. Present proposal for Detector Layout Secondary Junction Boxes tower NEMO will be modular detector: 1st Secondary JB … … Nst Secondary JB 8 10 towers Main JB electro-optical cables network 8 10 towers Primary Junction Box Electro-optical cable from shore • 1 main Junction Box • 8  10 secondary Junction Boxes • 60  80 towers • 140  200 m between each tower • 16  18 floors for each tower • 64  72 PMT for each tower • 4000  6000 PMTs The tower geometry allows: good sensitivity to 100 GeV neutrinos Aeff > 1 km2 at E ~10 TeV feasibility of underwater operations Several layouts under study Changes: distances, number of towers, tower length, shape (hexagonal), …

  23. Expected detector performaces Sensitivity Sensitivity to point like fluxes Ev-2 spectrum Geometry “flexibility” Effective area for different detector geometries spacing spacing towers floors 140 m 40 m 300 m 40 m NEMO 81 towers 140m spaced - 5832 PMTs IceCube 80 strings 125m spaced - 4800 PMTs

  24. The NEMO Phase 1 The NEMO Collaboration is undergoing the Phase 1 of the project, installing a fully equipped deep-sea facility to test prototypes and develop new technologies for the km3 detector. An electro-optical cable (10 fibres, 4 conductors) connects the shore laboratory, in the Port of Catania, with the underwater test site Underwater test site: 25 km E offshore Catania at 2000 m depth Shore laboratory port of Catania To be completed in 2006 e.o. cable from shore NEMO mini-tower (4 floors) TSS Frame Junction Box underwater e.o. cable

  25. The NEMO test site: a multidisciplinary laboratory • First data from 2000 m • GEOSTAR SN-1, a deep sea station for on-line seismic and environmental monitoring by INGV. The NEMO test site is the Italian site for ESONET (European Seafloor Observatory NETwork); • ODE (Ocean noise Detection Experiment), for on-line deep sea acoustic signals monitoring (4 hydrophones hydrophones 30 Hz - 40 kHz  measurement of noise bkg for neutrino acoustic detection ). The ODE station GEOSTAR SN-1 deep sea station

  26. NEMO Phase-1: scheme and deployment schedule Deployment of JB and minitower summer 2006 Deployedjanuary 2005 Mini-Tower unfurled NEMO mini-tower (4 floors, 16 OM) 300 m TSS Frame Junction Box Mini-Tower compacted 15 m

  27. The Junction Box The Junction Box hosts the data transmission and power distribution system Power vessels electro-optical connector Fiberglass external vessel 1 m This solution permits to separate the corriosion and the pressure resistance problems

  28. The tower Tower assembly at test site Optical modules Floor control module

  29. The NEMO Phase 2 project in Capo Passero Portopalo di Capo Passero • Goals • Realization of an underwater infrastructure at 3500 m on the CP site • Test of the detector structure installation procedures at 3500 m • Installation of a 16 storey tower • Long term monitoring of the site • Infrastructure • A building (1000 m2) located inside the harbour area of Portopalo has been acquired. It will be renewed to host the shore station for power supply and data acquisition systems • 100 km electro-optical cable (about 40 kW) purchsed. Deployment by Alcatel-Elettra. • Project completion planned in 2007

  30. KM3NeT Partecipants: 34 istitutes from 8 countries Obiettivo: design study for a submarine high energy observatory open to multidisciplinary submarine science Start 2006. Finish 2009. Total Budget 20278 k€, UE funding 9000 k€ Physics Analysisand simulations System and Product Engineering WORK PACKAGES Information Technology Shore and deep-sea infrastructure Sea surface infrastructure Risk Assessment Quality Assurance Resource Exploration Associated Science Technical Design Report (and recommendation on installation site)

  31. Summary • First generation detectors Baikal and AMANDA have demonstrated the feasibility of the high energy neutrino detection; • The forthcoming km3 neutrino telescopeswill be “discovery” detectors with potential to solve HE astrophysics basic questions: • UHECR sources, HE hadronic mechanisms, Dark matter ... • To fully exploit neutrino astronomy we need two km3 scale detectors, one for each hemisphere; • The under-ice km3ICECUBE is under way, following the AMANDA experience; • The Mediterranean km3 neutrino telescope will be an powerful astronomical observatory thanks to its excellent angular resolution; KM3Net feasibility study for the km3 detector started on beginning of 2006; • ANTARES deployed Line1 on Feb. 2006, atmospheric muons already reconstructed; • NEMO is installing the Test Site in Catania and building infrastructures in Capo Passero.

  32. NEMO in Capo Passero

  33. The NEMO Collaboration INFN Bari, Bologna, Catania, Genova, LNF, LNS, Napoli, Pisa, Roma Università 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) Circa 100 ricercatori dell’INFN e dei principali enti di ricerca italiani coinvoltii

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