1 / 39

The ANTARES Underwater Neutrino Telescope

The ANTARES Underwater Neutrino Telescope. C.W. James, ECAP, University of Erlangen, on behalf of the ANTARES collaboration. Cosmic rays and neutrinos. What produces this spectrum? Standard model: acceleration at relativistic astrophysical shocks. R. Shellard , Braz. J. Phys 31 (2001) .

kevlyn
Download Presentation

The ANTARES Underwater Neutrino Telescope

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The ANTARES Underwater Neutrino Telescope C.W. James, ECAP, University of Erlangen, on behalf of the ANTARES collaboration.

  2. Cosmic rays and neutrinos • What produces this spectrum? • Standard model: acceleration at relativistic astrophysical shocks R. Shellard, Braz. J. Phys 31 (2001)

  3. Why look for neutrinos? • Flux unattenuated over cosmological distances • Travel in straight lines (unlike cosmic rays) • Signatures of hadronic processes in the high-energy universe SNR GRB AGN jets and lobes Image courtesy of NRAO/AUI Image courtesy of NRAO/AUI NASA/Swift/Stefan Immler Nature 432 (2004) 75

  4. Quick note: these are not Solar neutrinos! • Production via cosmic-ray (~proton) interactions with: • Much rarer than solar neutrinos – but more energetic (GeV-PeV: not MeV) • νμ and ντ CC interactions possible low E proton Hadronic matter (interstellar gas) Photon fields (CMB)

  5. 3D PMTarray Cherenkov light from m 42° Earth’s crust (sea floor; Antarctic continent) m nm interaction Detection Principle p, a nm Optically transparent material (water; deep ice) p m nm nm Main detection channel: CC interactions ( NC, ande and  also). 5

  6. Let’s build it!

  7. The ANTARES Collaboration • University of Erlangen • Bamberg Observatory • Univ. of Wurzeburg • NIKHEF, • Amsterdam • Utrecht • KVI Groningen • NIOZ Texel • ITEP,Moscow • MoscowStateUniv • IFIC, Valencia • UPV, Valencia • UPC, Barcelona • ISS, Bucarest 8 countries 31 institutes ~150 scientists+engineers • CPPM, Marseille • DSM/IRFU/CEA, Saclay • APC, Paris • LPC, Clermont-Ferrand • IPHC, Strasbourg • Univ. de H.-A., Mulhouse • LAM, Marseille • COM, Marseille • GeoAzurVillefranche • INSU-DivisionTechnique • LPRM, Oujda • Univ./INFN of Bari • Univ./INFN of Bologna • Univ./INFN of Catania • LNS–Catania • Univ./INFN of Pisa • Univ./INFN of Rome • Univ./INFN of Genova 7

  8. ANTARES: Location • 40km off the coast of Toulon

  9. V. Bertin - CPPM - ARENA'08 @ Roma 2500m 450 m 70 m The ANTARES detector • 12lines • 25 storeys/line • 3 PMTs / storey • 885 10-inch PMTs • 10-20 Mton volume 40 km to shore Junction Box Interlink cables

  10. Sample events • Maximum-likelihood fit to recorded photon hit times http://www.pi1.physik.uni-erlangen.de/antares/online-display/online-display.php

  11. CRAB VELA SS433 ANTARES ‘visibility’ • ANTARES at 43o N • Sensitive to the Southern sky • Includes the Galactic Centre Never visible Invisible Increasing sensitivity ANTARES: 43o N Mkn 501 RX J1713.7-39 GX339-4 Galactic Centre Visible Always visible

  12. ANTARES performance: angular resolution • ~50% events reconstruct to better than 0.5o • ~99% reconstruct to better than 10o • Energy reconstruction is much harder (most is not ‘seen’) m n

  13. Muon and neutrino backgrounds • Remove atmospheric muon background with quality cuts • CR neutrino background irreducible p, a nm m p 1% misreconstruction Look for an excess here! Muon flux at 2500m depth from below from above

  14. Science with ANTARES • High-energy Neutrino Astrophysics • Galactic sources: SN & SNR, micro-quasars, CR in molecular clouds • Extra-galactic sources: AGN, GRB, GZK processes • Search for new physics: • Dark matter annihilation, nuclearites, monopoles • Earth sciences: • Oceanography, marine biology, seismology, environment monitoring… Oscillations DM SNR, μQSO AGN Exotics, GZK Marine biology GUT???

  15. Results!

  16. All-sky point-source search • Sky map in equatorial coordinates: • 2007-2010 data (813 days livetime) • 3058 candidates after cuts: expect 14% down-going muon contamination Most significant cluster: 2.2σ No strong evidence for a point-source excess

  17. Search from suspected sources • 51 pre-defined ‘suspect’ sources (mostly based on gamma-ray flux and visibility) • Top 11 sources: most significant first WR20a & b: hot, massive stars HESS, Astronomy & Astrophysics 467 (2007) 1075

  18. Neutrinos from gamma-ray bursts • ‘Fireball’ model for GRBs: • Explains long-duration bursts • Predicts neutrinos! • Search criteria: • Direction (2o from source) • Time (~1 minute) • Upcoming events only • Results from 2007 data (40 GRBs): no detection

  19. Neutrino Oscillations • Two-flavour mixing approximation: • Measureable: ‘Unknown’: • World data: 1st minimum at , (120 m max muon range) • Expectations for 863 days’ data: Events seen with two lines Events seen with one line No oscillations Best world data

  20. Oscillation analysis: results • After a Chi2minimisation to and two systematic variables: • 1st measurement of its type • Accepted July 2nd by Physics Letters B • Promising for next-generation larger detectors Combined single and multi-line data ANTARES K2K MINOS Super-K Data No oscillations Best fit 90% C.L. 68% C.L.

  21. Muon Flux Limits 90%CL (2007-2008) Search for Dark Matter Annihilation in the Sun • Lack of excess: => model limits (apologies: I do not have these plots here!) • A search for an excess from the galactic centre is ongoing  PRELIMINARY Angular distance from sun 21

  22. Search for magnetic monopoles • Relativistic monopoles emit VC radiation • 8550 times brighter than a muon • Look for extremely bright events! • ANTARES search space • Relativistic • ‘intermediate mass’ (< 1014GeV) • Search performed on data from 2008: • 1 event • 0.13 bkgd • 1.5 σ significance

  23. Multi-Messenger astronomy • Strategy: • Increase discovery potential (different probes) • Increase significance via coincidence Alerts • Ligo/Virgo (grav. waves) • Dedicated analysis chain • GW trigger • GCN (GRB) • Global burst network • GRB burst alert • ANTARES trigger and coincident analysis • TAROT (optical) • Follow-up search for SN • 10s repositioning

  24. Summary • ANTARES underwater neutrino telescope: • Largest neutrino telescope in the Northern Hemisphere • Proven ability to detect neutrino-induced muons • Good performance in bread & butter science: neutrino astrophysics • Sensitivity optimised for the galactic centre region • Diverse physics program: • Dark matter • Neutrino oscillations • Exotics (magnetic monopoles, nuclearites) • Entering ‘mature’ phase: • First round of results published (~1 year’s data) • Analyses on 3+ years of 12-line data in progress • More results on their way!

  25. (in case of tricky questions) Extra Slides

  26. Background and diffuse flux sensitivity • High energies favour source spectra • Background from atmospheric neutrinos: Enu-3.7 • Sources: order Enu-2 • Look for a high-energy excess! Limits on an E-2 flux E2F(E)90%= 5.3×10-8 GeV cm-2 s-1 sr-1 20 TeV<E<2.5 PeV Energy estimation: the ‘R’ parameter

  27. Standard data pipeline • ‘hit’: send PMT data to shore when one or more photons are observed • Raw data rate: too high to record • Trigger: Record data to disk if it looks `interesting’. • Standard trigger requirements: • Large ( ) hits OR hits on neighbouring PMTs (600 Hz) • Clusters of >=5 hits • Trigger hits must be causally connected • Many other triggers (GRB alert, monitoring info, GC etc) Threshold: 0.3 Vphoton PMT voltage Shore triggering and data acquisition 25 ns integration

  28. Candidate List Search – 90%CL Flux Limits Assumes E-2 flux for a possible signal ANTARES 2007-2010 813 days ANTARES has the most stringent limits for the Southern Sky

  29. Optical Background • Potassium 40 decay: constant background • Bioluminescence: large seasonal fluctuations • Bacteria • Vertebrates Image courtesy Wolfram Alpha Spring 2006 Spring 2007

  30. Trigger effective area • (preliminary plot: officially updated version will be out shortly)

  31. Data reduction for point-source search • Cut on angular-error estimate, and on fit quality

  32. Resolution: use the Moon’s shadow • The Moon blocks CR: expect reduction in the upcoming-event rate • 884 days’ livetime • 2.7 sigma defecit • Agrees with Monte Carlo expectations

  33. Storey 1 Storey 8 Storey 14 Storey 20 Storey 25 Sea currents and acousticpositioning Measure every 2 min: Distance line bases to 5 storeys/line and also storey headings and tilts Radial displacement Precision~ few cms

  34. 2006 – 2008: Building phase of the Detector ~70 m Junction box 2001 Main cable 2002 Line 1, 22006 Line 3, 4, 501 / 2007 Line 6, 7, 8, 9, 1012 / 2007 Line 11, 1205 / 2008

  35. Search for Neutrinos from Fermi Bubbles For 100% hadronicmodels: F ~1/2.5 F (Vissani) E2dF/dE=1.2*10-7 GeV cm-2s-1sr -1 E cutoff protons: 1PeV-10 PeV (Croker&Aharonian) E cutoff neutrinos = 1/20 cutoff protons Good visibility for ANTARES detector coords galacticcoords Background estimatedfrom average of three ‘OFF’ regions (time shifted in local coordinates)

  36. DarkMatterSimulation MWIMP = 350 GeV M A I N A N N I H I L A T I O N C H A N N E L S mUEDparticular case… τ leptons regeneration in the Sun

  37. Dark matter – detector performance • ANTARES effective area to muon neutrinos incident on Earth • Most neutrinos do not produce detectable muons • Most muons are very low in energy

  38. Magnetic Monopoles: data reduction • Magnetic monopoles… • Theoretical prediction (quantisation of charge, guage theories…) • Have not been observed (various limits exist) • Have a magnetic charge g: will emit Vavilov-Cherenkov radiation • VC radiation: 8550 times brighter than that of a muon with similar velocity • Acceleration in cosmic magnetic fields

  39. Muon Flux Limits 90%CL (2007-2008) Search for Dark Matter Annihilation in the Sun  PRELIMINARY Angular distance from sun PRELIMINARY 39

More Related