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Neutrino Telescopy in the Deep Sea

Neutrino Telescopy in the Deep Sea. Elementary Particle Physics Seminar, University of Oxford. Uli Katz Univ. Erlangen 05.06.2007. Introduction Physics with Neutrino Telescopes ANTARES and Other Current Projects Aiming at a km 3 Detector in the Mediterranean Sea: KM3NeT

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Neutrino Telescopy in the Deep Sea

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  1. Neutrino Telescopy in the Deep Sea Elementary Particle Physics Seminar, University of Oxford Uli Katz Univ. Erlangen 05.06.2007 Introduction Physics with Neutrino Telescopes ANTARES and Other Current Projects Aiming at a km3 Detector in the Mediterranean Sea: KM3NeT Conclusions and Outlook

  2. ~E-2.7 knee 1 part m-2 yr-1 ~E-3 ~E-2.7 ankle 1 part km-2 yr-1 LHC The Mysterious Cosmic Rays • Particles impinging on Earth from outer space carry energies up to1021 eV(the kinetic energy of a tennis ball at ~200km/h.) • The acceleration mechanisms are unknown. • Cosmic rays carry a significant fraction of the energy of the universe – cosmologically relevant! • Neutrinos play a key role in studying the origin of cosmic rays. U. Katz: Neutrino Telescopy in the Deep Sea

  3. Neutrino Production Mechanism • Neutrinos are expected to be produced in the interaction of high energy nucleons with matter or radiation: Cosmic rays • Simultaneously, gamma production takes place: Cosmic rays • Cosmic ray acceleration yields neutrinos and gammas • … but gammas also from purely leptonic processes U. Katz: Neutrino Telescopy in the Deep Sea

  4. protons E>1019 eV (10 Mpc) neutrinos gammas (0.01 - 1 Mpc) protons E<1019 eV Particle Propagation in the Universe Cosmic accelerator 1 parsec (pc) = 3.26 light years (ly) Photons: absorbed on dust and radiation; Protons/nuclei: deviated by magnetic fields, reactions with radiation (CMB) U. Katz: Neutrino Telescopy in the Deep Sea

  5. The Principle of Neutrino Telescopes Cherenkov light: • In water: θC≈ 43° • Spectral range used: ~ 350-500nm. Role of the Earth: • Screening against all particlesexcept neutrinos. • Atmosphere = target for productionof secondary neutrinos. Angular resolution in water: • Better than ~0.3° for neutrino energy above ~10 TeV, 0.1° at 100 TeV • Dominated by angle(n,m) below ~10 TeV (~0.6° at 1 TeV) U. Katz: Neutrino Telescopy in the Deep Sea

  6. Neutrino Interaction Signatures • Neutrinos mainly from π-µ-e decays,roughly ne : nµ : nt = 1 : 2 : 0; • Arrival at Earth after oscillations:ne : nµ : nt≈ 1 : 1 : 1; • Key signature: muon tracksfromnµcharged current reactions(few 100m to several km long); • Electromagnetic/hadronic showers: “point sources” of Cherenkov light. muon track hadronic shower electromagn. shower hadronic shower hadronic shower U. Katz: Neutrino Telescopy in the Deep Sea

  7. Muon Reconstruction • The Cherenkov light is registered by the photomultipliers with nanosecond precision. • From time and position of the hits the direction of the muon can be reconstructed to ~0.1°. • Minimum requirement: 5 hits … in reality rather 10 hits. • Position calibration to ~10cm required (acoustic methods). 1.2 TeV muon traversing the detector. U. Katz: Neutrino Telescopy in the Deep Sea

  8. Muons: The Background from Above Muons can penetrate several km of water if Eµ > 1TeV; Identification of cosmic n‘s from above: needs showers or very high energies. U. Katz: Neutrino Telescopy in the Deep Sea

  9. Neutrinos from Astrophysical Point Sources • Association of neutrinos to specific astrophysical objects. • Energy spectrum, time structure, multi-messenger observations provide insight into physical processes inside source. • Measurements profit from very good angular resolution of water Cherenkov telescopes. • km3 detectors neededto exploit the potential of neutrino astronomy. KM3NeT, IceCube Northern Sky Southern Sky U. Katz: Neutrino Telescopy in the Deep Sea

  10. Sky Coverage of Neutrino Telescopes Observed sky region in galactic coordinates assuming efficiency for downwardhemisphere. Mediterranean site: >75% visibility >25% visibility → We need Northern n telescopes to cover the Galactic Plane U. Katz: Neutrino Telescopy in the Deep Sea

  11. Example candidate accelerators: Active Galactic Nuclei (AGNs) AGNs are amongst the most energeticphenomena in theuniverse. U. Katz: Neutrino Telescopy in the Deep Sea

  12. IceCube/AMANDA data 3.7s excess 69 out of 100 randomsky maps have an excesshigher than 3.7s Do AMANDA/IceCube see Point Sources? Random points IceCube/AMANDA data 2000-2004 • 4282 neutrino events in 1001 days live-time • Sky map of excess significance • Presented by Gary Hill at the Neutrino 2006 conference, Santa Fe U. Katz: Neutrino Telescopy in the Deep Sea

  13. High-energy g sources in the Galactic Disk Update June 2006: • 6 g sources could be/are associated with SNR, e.g. RX J1713.7-3946; • 9 are pulsar wind nebulae, typically displaced from the pulsar; • 2 binary systems(1 H.E.S.S. / 1 MAGIC); • 6 have no known counterparts. W. Hofmann, ICRC 2005 U. Katz: Neutrino Telescopy in the Deep Sea

  14. Example: SNR RX J1713.7-3946(shell-type supernova remnant) H.E.S.S. : Eg=200 GeV – 40 TeV • Accelerationbeyond 100 TeV. • Power-law energyspectrum, index ~2.1–2.2. W. Hofmann, ICRC 2005 Example: n’s from Supernova Remnants • Spectrum points to hadron acceleration  n flux ~ g flux • Typical n energies: few TeV U. Katz: Neutrino Telescopy in the Deep Sea

  15. Precise n Flux Predictions from g ray Measurements • Kappes et al., • astro-ph 0607286 Vela X (PWN) measured-ray flux (H.E.S.S.) mean atm. flux(Volkova, 1980, Sov.J.Nucl.Phys., 31(6), 784) expected neutrino flux –in reach for KM3NeT • 1  error bands include systematic errors (20% norm., 10% index & cut-off) U. Katz: Neutrino Telescopy in the Deep Sea

  16. Indirect Search for Dark Matter • WIMPs can be gravitationally trapped in Earth, Sun or Galactic Center; • Neutrino production by • Detection requires low energy threshold. • Example: n flux (E > 10GeV) from Sun in scan of mSugra parameter space[ m0 < 8TeV, m1/2 < 2TeV, sign(m)=+, |A0| < 3m0, 0 < tan(b) < 60] Holger Motz, Univ. Erlangen ● All models ● 0.094 < Wh2 < 0.139 (WMAP 2s) ● Wh2 < 0.094 U. Katz: Neutrino Telescopy in the Deep Sea

  17. Dark Matter sensitivity estimates for KM3NeT Note: Specific assumptions on KM3NeTsize, geometry and photo-detection used. • Blue: Excludable only by KM3NeT(3 years, 90%C.L.) • Black: Excludable only by CDMS-2007 • Green: Excludable by both • Red: Not excludable Holger Motz, Univ. Erlangen. U. Katz: Neutrino Telescopy in the Deep Sea

  18. 2002 RICE GLUE 2004 Topological defects (Sigl) Waxman-Bahcall bound (n oscillation corrected) Extragalactic gp sources (Mannheim et al.) 2007 AGN Jets (Mannheim) Gamma Ray Bursts(Waxman & Bahcall) GZK neutrinos (Rachen & Biermann) Diffuse n Flux: Models, Limits and Sensitivities RICE AGASA • At En≈100 TeV the Earth starts to be opaque for n’s  required to look upwards; • Upward shielding important; • GRBs & other transients: Time correlations can improve sensitivity significantly. C. Spiering, J. Phys. G 29 (2003) 843 Amanda, Baikal Anita AUGER nt Amanda,Antares, Baikal, Nestor Auger + new technologies 2012 km3 U. Katz: Neutrino Telescopy in the Deep Sea

  19. Directn-g connection Astro- and Particle Physics with n Telescopes • High-energy limit: • neutrino flux decreases like E–n (n ≈ 2) • large detectionvolume needed. • Low-energy limit: • detector sensitivity • background U. Katz: Neutrino Telescopy in the Deep Sea

  20. The Neutrino Telescope World Map ANTARES + NEMO + NESTORjoin their efforts to preparea km3-scale neutrino telescope in the MediterraneanKM3NeT Design Study U. Katz: Neutrino Telescopy in the Deep Sea

  21. ANTARES: Detector Design • String-based detector; • Underwater connectionsby deep-sea submersible; • Downward-lookingphotomultipliers (PMs),axis at 45O to vertical; • 2500 m deep. 25 storeys, 348 m 14.5m 100 m Junction Box ~70 m U. Katz: Neutrino Telescopy in the Deep Sea

  22. ANTARES: Detector Strings • Buoy:− buoyancy ~6400 N;− keeps string vertical to better than 20m displacement at top. • Electro-optical-mechanical cable:− metal wires for power supply etc.;− optical fibers for data;− mechanical backbone of string. • Storeys:− 3 optical modules per storey;− titanium cylinder for electronics;− calibration devices (light, acoustics). • Anchor:− deadweight to keep string at bottom;− release mechanism operated by acoustic signal from surface. U. Katz: Neutrino Telescopy in the Deep Sea

  23. Optical Module LED Beaconfor time calibrationpurposes Titanium cylinder housing electronics forreadout, calibration, … Hydrophone (RX)for positioning ANTARES: Components of a Storey U. Katz: Neutrino Telescopy in the Deep Sea

  24. ANTARES: Optical Modules • Photomultipliers:− transfer time spread ~2.7ns (FWHM);− quantum efficiency >20% for330 nm < λ < 460nm; • Glass spheres:− qualified for 600 bar; Hamamatsu 10´´ PM 43 cm U. Katz: Neutrino Telescopy in the Deep Sea

  25. ANTARES Construction Milestones 2001 – 2003: • Main Electro-optical cable in 2001 • Junction Box in 2002 • Prototype Sector Line (PSL) & Mini Instrumentation Line (MIL) in 2003 2005 – Now: • Mini Instrumentation Line with OMs (MILOM) running since 12 April 2005 • Lines 1-5 running (connected between March 2006 and Jan. 2007) • Lines 6+7 deployed March/April 2007 • 2007+: • Deployment / connection of remaining 5(7) lines • Replacement of MILOM by full instrumentation line (IL) • Physics with full detector ! U. Katz: Neutrino Telescopy in the Deep Sea

  26. ANTARES: First Detector line installed … 14. Feb. 2006 U. Katz: Neutrino Telescopy in the Deep Sea

  27. … and connected by ROV Victor! 2. March 2006(ROV = Remotely operated submersible) U. Katz: Neutrino Telescopy in the Deep Sea

  28. Baseline (40K+biolum.) ANTARES: Data from 2500m Depth (MILOM) Bursts frombioluminescence 2 minutes • Background light: • bioluminescence (bacteria, macroscopic organisms) • decays of 40K (~30 kHz for 10’’ photomultiplier) • Correlation with water current • Light bursts by macroscopic organisms – induced by pressure variation in turbulent flow around optical modules ?! Burst-fraction:fraction of time whenrate > baseline + 20% U. Katz: Neutrino Telescopy in the Deep Sea

  29. 10.5±0.4 Hz 13.0±0.5 Hz 13.0±0.5 Hz ANTARES: Coincidence rates from 40K decays γ Simulation: 12 Hz ± 4 Hz (sys) 40Ca γ(Cherenkov) e- (b decay) 40K U. Katz: Neutrino Telescopy in the Deep Sea

  30. s = 2.6 ns • "diagonal" • larger distance • less intensity • light scattering s = 0.7 ns "horizontal" Dt [ns] ANTARES: Time Calibration with LED Beacons Line 1 all timing measurements in good agreement with expectations MILOM ~150 m ~70 m U. Katz: Neutrino Telescopy in the Deep Sea

  31. μ ANTARES: First Atmospheric Muons … c2 minimisation to find zenith angle of track • Run 21240 / Event 12505 • Zenith θ= 101o • P(c2,ndf) = 0.88 • Triggered hits • Hits used in fit • Snapshot hits + Hit altitude (relative to mid detector) [m] ANTARESpreliminary Hit time [ns] U. Katz: Neutrino Telescopy in the Deep Sea

  32. … and Events with 5 Lines! Very preliminary! First neutrinos ... ?! U. Katz: Neutrino Telescopy in the Deep Sea

  33. NESTOR: Rigid Structures Forming Towers Plan: Tower(s) with12 floors →32 m diameter →30 m between floors →144 PMs per tower • Tower based detector(titanium structures). • Dry connections(recover − connect − redeploy). • Up- and downward looking PMs (15’’). • 4000 m deep. • Test floor (reduced size) deployed & operated in 2003. • Deployment of 4 floors planned in 2007 U. Katz: Neutrino Telescopy in the Deep Sea

  34. NESTOR: Data from the Deep Sea • Background baseline rate of 45-50 kHz per PM • Bioluminescence bursts correlated with water current, on average 1.1% of the time. low current high current NESTOR Coll., G Aggouras et al, Nucl. Inst. Meth, A552 (2005) 420 • Trigger rates agree with simulation including background light. • For 5-fold and higher coincidences, the trigger rate is dominated by atmospheric muons. measured rates MC simulation MC, atm. muons Threshold 30mV U. Katz: Neutrino Telescopy in the Deep Sea

  35. NESTOR: Measurement of the Muon Flux NESTOR Coll., G Aggouras et al, Astropart. Phys. 23 (2005) 377 Atmospheric muon flux determination and parameterisation by Muon intensity (cm-2s-1sr-1) • = 4.7  0.5(stat.)  0.2(syst.) I0 = 9.0  0.7(stat.)  0.4(syst.) x 10-9 cm-2 s-1 sr-1 (754 events) Results agree nicelywith previous measurements and with simulations. Zenith Angle (degrees) U. Katz: Neutrino Telescopy in the Deep Sea

  36. The NEMO Project • Extensive site exploration(Capo Passero near Catania, depth 3500 m); • R&D towards km3: architecture, mechanical structures, readout, electronics, cables ...; • Simulation. Example: Flexible tower • 16 arms per tower, 20 m arm length,arms 40 m apart; • 64 PMs per tower; • Underwater connections; • Up- and downward-looking PMs. U. Katz: Neutrino Telescopy in the Deep Sea

  37. Geoseismic station SN-1 (INGV) Shore station 5 km e.o. cable 21 km e.o. Cable with single steel shield J J BU J 2.5 km e.o. Cable with double steel shield 5 km e.o. cable • January 2005: Deployment of • 2 cable termination frames(validation of deep-sea wet-mateable connections) • acoustic detection system(taking data). • 10 optical fibres standard ITU- T G-652 • 6 electrical conductors  4 mm2 NEMO Phase I: Current Status • Test site at 2000 m depth operational. December 2006: Deployment of • one Junction Box • one prototype tower(5 storeys) Data taking ongoing! U. Katz: Neutrino Telescopy in the Deep Sea

  38. NEMO Phase-1: Some Elements Dec. 2006: Deployment of JB and mini-tower DeployedJanuary 2005 Junction Box (JB) NEMO mini-tower (4 floors, 16 OM) 300 m TSS Frame Mini-tower, unfurled Mini-tower, compacted 15 m U. Katz: Neutrino Telescopy in the Deep Sea

  39. How to Design a km3 Deep-Sea n Telescope • Existing telescopes “times 30” ? • Too expensive • Too complicated(production, maintenance) • Not scalable(readout bandwidth, power, ...) scale up new design dilute • R&D needed: • Cost-effective solutionstoreduce price/volume by factor ~2 • Stabilitygoal: maintenance-free detector • Fast installationtime for construction & deploymentless than detector life time • Improved components • Large volume with same number of PMs? • PM distance: given by absorption length inwater (~60 m) and PM properties • Efficiency loss for larger spacing U. Katz: Neutrino Telescopy in the Deep Sea

  40. KM3NeT Design Study: The last years Design Study for a Deep-Sea Facility in the Mediterranean for Neutrino Astronomy and Associated Sciences • Initial initiative Sept. 2002. • VLVnT Workshop, Amsterdam, Oct. 2003. • ApPEC review, Nov. 2003. • Inclusion of marine science/technology institutes (Jan. 2004). • Proposal submitted to EU 04.03.2004. • Confirmation that Design Study will be funded (Sept. 2004). • KM3NeT on ESFRI list of Opportunities, March 2005. • 2ndVLVnT Workshop, Catania, 08-11.11.2005. • Design Study contract signed, Jan. 2006 (9 M€ from EU, ~20 M€ overall). • Start of Design Study project, 01.02.2006. • Kick-off meeting, Erlangen, April 2006. • KM3NeT on ESFRI Roadmap, Sept. 2006 • First annual meeting, Pylos, April 2007 And: Essential progress of ANTARES, NEMO and NESTOR in this period! U. Katz: Neutrino Telescopy in the Deep Sea

  41. KM3NeT Design Study: Participants • Cyprus: Univ. Cyprus • France: CEA/Saclay, CNRS/IN2P3 (CPP Marseille, IreSStrasbourg, APC Paris-7), Univ. Mulhouse/GRPHE,IFREMER • Germany: Univ. Erlangen, Univ. Kiel • Greece: HCMR, Hellenic Open Univ., NCSR Demokritos, NOA/Nestor, Univ. Athens • Ireland: Dublin Institute of Advanced Studies (since 1.Nov.2006) • Italy: CNR/ISMAR, INFN (Univs. Bari, Bologna, Catania, Genova, Napoli, Pisa, Roma-1, LNS Catania, LNF Frascati), INGV, Tecnomare SpA • Netherlands: NIKHEF/FOM (incl. Univ. Amsterdam, Univ. Utrecht, KVI Groningen) • Romania:ISS Bucharest (since 1.June 2007) • Spain: IFIC/CSIC Valencia, Univ. Valencia, UP Valencia • UK: Univ. Aberdeen, Univ. Leeds, Univ. Liverpool, Univ. Sheffield Particle/Astroparticle institutes (29+1) –Sea science/technology institutes (7)–Coordinator U. Katz: Neutrino Telescopy in the Deep Sea

  42. The KM3NeT Design Study work packages • WP1: Management of the Design Study • WP2: Physics analysis and simulation • WP3: System and product engineering • WP4: Information technology • WP5: Shore and deep-sea infrastructure • WP6: Sea surface infrastructure • WP7: Risk assessment and quality assurance • WP8: Resource exploration • WP9: Associated sciences U. Katz: Neutrino Telescopy in the Deep Sea

  43. The KM3NeT Vision • KM3NeT will be a multidisciplinary research infrastructure: • Data will be publicly available; • Implementation of specific online filter algorithms willyield particular sensitivity in predefined directions non-KM3NeT members can apply for observation time; • Data will be buffered to respond to GRB alerts etc. • Deep-sea access for marine sciences. • KM3NeT will be a pan-European project • 8+2 European countries involved in Design Study; • Substantial funding already now from national agencies. • KM3NeT will be constructed in time to take dataconcurrently with IceCube. • KM3NeT will be extendable. Target price tag: 200 M€/km3 or less U. Katz: Neutrino Telescopy in the Deep Sea

  44. Some Key Questions All these questions are highly interconnected ! • Which architecture to use?(strings vs. towers vs. new design) • How to get the data to shore?(optical vs. electric, electronics off-shore or on-shore) • How to calibrate the detector?(separate calibration and detection units?) • Design of photo-detection units?(large vs. several small PMs, directionality, ...) • Deployment technology?(dry vs. wet by ROV/AUV vs. wet from surface) • And finally: The site question U. Katz: Neutrino Telescopy in the Deep Sea

  45. 200 m Top view 20 x 60 m = 1200 m Top view 250 m 200 m 250 m 20 m 20 x 60 m = 1200 m 20 x 60 m = 1200 m 40 m 50 x 20 m = 1000 m 16 x 40 m = 640 m 50 floors 20 m step 16 floors, 4 PMs each 40 m step homogeneous lattice of 20 x 20 x 20 downward-looking 10-inch photomultiplier tubes 25 towers, each consists of 7 strings PMs are directed downwards 64 NEMO-like towers Detector Architecture (D. Zaborov at VLVnT) U. Katz: Neutrino Telescopy in the Deep Sea

  46. Sea Operations • Rigid towers or flexible strings? • Connection in air (no ROVs) or wet mateable connectors? • Deployment from platform or boat? U. Katz: Neutrino Telescopy in the Deep Sea

  47. Photo Detection: New ideas … • Idea: Use multiple small (3-inch) photomultipliers in one glass sphere • Improves signal-to-noise ratio • Improves single-to-multiple photo-electron separation • Increases photocathode area and possibly quantum efficiency • But: cost and readout issues need to be studied. U. Katz: Neutrino Telescopy in the Deep Sea

  48. Observatories KM3NET 2 Observatory Data Junction Box 1 Array Data Associated Sciences node Test Site 3 Test Data Junction Box Control Signals Cable to shore Fixed Cable ROV Moveable tether Associated Sciences Node M. Priede, Sept. 2005 U. Katz: Neutrino Telescopy in the Deep Sea

  49. KM3NeT: Path to Completion Time schedule (partly speculative & optimistic): 01.02.2006 Start of Design Study Fall 2007 Conceptual Design Report February 2009 Technical Design Report 2008-2010 Preparatory Phase in FP7 2010-2012 Construction 2011-20xxData taking Proposal submitted on May 2, 2007 U. Katz: Neutrino Telescopy in the Deep Sea

  50. Next Step: The Preparatory Phase Project • Top-down call, restricted to ESFRI projects • Objective: Pave the way to construction of ESFRI RIs • Political and financial convergence • Legal / governance structure • Strategic preparation (centers of excellence, user needs, data dissemination etc.) • Technical work (production preparation) • Financial framework: • 135 M€ for 30-35 projects  ~4 M€ / project on average • KM3NeT proposal: ~6.8 M€ U. Katz: Neutrino Telescopy in the Deep Sea

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