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Results from the ANTARES Deep Sea Neutrino Telescope. Maurizio Spurio On behalf of the ANTARES Collaboration Università di Bologna and INFN. Science with Deep Sea Neutrino Telescopes. High energy neutrino astrophysics : galactic : SN, SNRs, m -quasars, molecular clouds, etc…
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Resultsfrom the ANTARES DeepSea Neutrino Telescope M.Spurio-MG13 @ Stokolm Maurizio Spurio On behalf of the ANTARES Collaboration Università di Bologna and INFN
Science with Deep Sea Neutrino Telescopes • High energy neutrino astrophysics: • galactic: SN, SNRs, m-quasars, molecular clouds, etc… • extra-galactic: AGNs, GRBs, choked-GRBs, GZK, etc.... • Search for New Physics: • Dark matter (Sun, Galatic Centre), Monopoles, nuclearites, ?? • Earth-Sea Science: oceanography,seabiology, seismology, environmental monitoring... SNR oscillations darkmatterm-quasarsGRBsmagnetic Fermi-bubbles monopole M.Spurio-MG13 @ Stokolm
Neutrinos and Multi-Messenger Astronomy Protons/ Cosmic Rays: • Detected on Earth up to extremely high energies: 108TeV • Hard to study sources due to deflection by magnetic fields Photons: • Produced in leptonic (synchrotron, IC) and hadronic (0) processes • Absorbedathigherenergies and large distances Neutrinos (and GW): • Unambiguous signature of hadronic acceleration • Not deflected by magnetic fields or absorbed by dust • Horizon not limited by interaction with CMB/IR • Can escape from region of high matter density • Can be time correlated with optical signals hadronicacceleratorsexist, but where? M.Spurio-MG13 @ Stokolm • leptonic vs hadronicmodels • identifyGalactic and extraGalactic • cosmic ray sources 3
Cosmic Rays, photons and neutrinos ee ee • Hadronic cascades (as for atmospheric showers) • p/A + p/ e::=1:2:0 sourcee::=1:1:1 Earth • Primary acceleration («Bottom-Up») • Stochastics shocks (Fermi mechanism) • Explosion /Accretion / Core collapse • Benchmark Extra Gal. n flux Waxman-Bahcall M.Spurio-MG13 @ Stokolm ~ 500 events /yr/ km2 • But HE also from electromagnetic processes • Synchrotron Inverse Compton
Detection Principle 3D PMTarray Cherenkov light from m 42° Sea floor m nm interaction p, a nm p m nm nm The reconstruction is based on local coincidences compatible with the Cherenkov light front • - Main channel: interaction giving an ultra-relativistic (e and also) • Energy threshold ~ 20 GeV- 24hr operation, more than half sky coverage
Physical Background sources Atmospheric muons: only downgoing Shield detector & reject downward goingmuons Atmospheric 109 per year Atmospheric 104 per year Cosmic 0-10 per year ? M.Spurio-MG13 @ Stokolm upgoing downgoing T. Chiarusi, M.S. Eur. Phys. Journal C (2010) 649-701 . arXiv:0906.2634
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
The ANTARES Site & Infrastructure -2475m Shore Station 40 km submarine cable FOSELEV Marine IFREMER Toulon Centre
The ANTARES Detector 2500m 450 m 70 m • ~20 Mtoninstrvol • 885 10inch PMTs • 12 lines • 25 storeys/line • 3 PMTs / storey 40 km to shore M.Spurio-MG13 @ Stokolm Junction Box Interlink cables
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
Earth and Sea Sciences Connected 30 Oct 2010 Secondary Junction Box O2, CTD, P BioCam Seismograph Turbidity Instrumentation module Currentmeter
Up- and down-going Events reconstructed down-going muondetected in all 12 detector lines: reconstructed up-going neutrino detected in 6/12 detector lines:
Region of Sky Observable by Neutrino Telescopes CRAB CRAB VELA SS433 SS433 IceCube (South Pole) ANTARES(43° North) Mkn 421 Mkn 501 Mkn 501 RX J1713.7-39 GX339-4 Galactic Centre Emphasis on study of Galactic sources
Selected ANTARES physics results • Cosmic sources searches • Diffuse flux from ExtraGalactic sources • Multimessenger approach and Gravitational Waves coincidences • Neutrino oscillations
1. Point Source Search • Neutrino candidates: Upgoing particles • Background for neutrinos: mis-reconstructed atmospheric muons • Track fit quality used to reject mis-reconstructed downgoing muons • Number of hits used as estimator of muon (~neutrino) energy upgoing Number of up-going events as a function of the track quality parameter L Angular distribution of well-reconstructed tracks
1. Angular Resolution for Neutrinos m n cumulative distribution of the angle between the true neutrino track and the reconstructed muon event (assuming E-2 spectrum). The median is 0.46° 83% of the events within 1° Full 12 line detector
1. Full-Sky Search (2007-2010) Sky map in equatorial coordinates (3058 candidates) Pre-trial prob Most significant cluster at: RA= ‒46.5°, δ= ‒65.0° 1⁰ M.Spurio-MG13 @ Stokolm 3⁰ . Nsig = 5 p-value=0.026 (post-trial) Significance = 2.2 σ Results compatible with the background hypothesis
1. Source Candidate List Look in the direction of a list of 51 predefined candidate sources (selection of sources mostly based on γ-ray flux and visibility) First eleven sources sorted by p-value. Last column shows the 90% CL upper limit on the flux (E / GeV)-2 GeV-1 cm-2 s-1 M.Spurio-MG13@ Stokolm HESS J1023‒575 most signal-like, p–value 41% (post trial) Compatible with the background hypothesis
1. Candidate List Search – 90%CL Limits • Assumes E-2 flux for a possible signal • ANTARES has the most stringent limits for the Southern Sky • Galactic sources expected to have energy cutoff- not visible to IceCube • 2016: expect limits to improve by another factor ~2.5 ANTARES 2016 M.Spurio-MG13 @ Stokolm
2. Diffuse nm flux Phys. Lett. B696 (2011) 16-22 E2F(E)90%= 5.3×10-8 GeV cm-2 s-1 sr-1 20 TeV<E<2.5 PeV IC40
2. Search for diffuse n from Fermi Bubbles • Fermi-LAT data provided evidence of the emission of HE g-rays with a high intensity E-2 spectrum from two large areas above and below the Galactic Center (the "Fermi bubbles"). • A hadronic mechanism has been proposed for this • g-rays emission making the Fermi bubbles promising sources of high-energy neutrinos Galacticcoords For 100% hadronicmodels: E2dF/dE=1.2*10-7 GeV cm-2s-1sr -1 Ecutoff protons: 1PeV-10 PeV Background estimatedfrom average of three ‘OFF’ regions (time shifted in local coordinates) Detector coords
2. Search for Neutrinos from Fermi Bubbles ANTARES preliminary • Live time = 588 days • Cutsoptimised for best MRF • and a cutoffat 100 TeV • Nback(OFF) = 90±5(stat)±3(sys) • Nsignal(ON) = 75 • No signal • excludefullyhadronic FB • model withoutcutoff • (90%CL F&C) • Future: full dataset and • improvedenergyestimator ON ZONE <OFF ZONE> ANTARES preliminary 50 TeV cutoff 100 TeV cutoff 500 TeV cutoff no cutoff dotted: model prediction solid: 90% CL limits
3. Multimessenger approach Strategy: higher discovery potential by observing different probes higher significance by coincidence detection higher efficiency by relaxed cuts MoUs for joint research Alerts TAROT ROTSE optical follow up: Ligo/Virgo Gravitationalwaves: trigger + dedicated analysischain GCN GRB Coord. Network: γ satellites arXiv:1205.3018 Astropart.Phys.35(2012) 530-536 arXiv:1103.4477 arXiv:1111.3473.
3. Search for GW coincident signal V. V. Elewycket al. Int.J.Mod.Phys. D18 (2009) 1655-1659 B. Baret et al. Astropart.Phys. 35 (2011) 1-7 B. Baret et al. arXiv:1112.1140. Searchstrategy Common data taking Done On going Instantaneous Antares+Ligo+Virgo commonview 0 1
3. 2007 DatasetAnalysis set limits on distance of occurrence of NS-BH and NS-NS mergers • Sub-optimal detectors • No dedicated optimisation NO DETECTION Distance withinwhichthereis a 90% detectionprobabilitywith a 1% false alarm rate per neutrino Di Palma et al. TAUP 2011 B. Bouhou et al.arXiv:1201.2840
3. Correlation with Gravitational Waves - plausible common sources (microquasars, SGR, GRBs) - discoverypotential for ‘hidden’ sources (e.g. failedGRBs) 2007 ANTARES 5-line detector 2009-2010 12-line detector 2015-2016 adv LIGO/VRIGO 2007: No statistical significant correlation ⇒ set limits on distance of occurrence of NS-BH and NS-NS mergers First joint ANTARES/LIGO/VIRGO publication: arXiv:1205.3018v2 2009-2010: expect to constrain fraction of star collapses accompanied by coincident emission of jets beamed towards Earth M.Spurio-MG13 @ Stokolm 26
4. Oscillations with Atmospheric Neutrinos L=2 REarthcos, from track fit E from muon range E<100 GeV MC truth M.Spurio-MG13 @ Stokolm • Oscillations maximal at En=24 GeV for vertical neutrinos • Dashed line: oscillation effect • Largereffect on single-line (lowenergy) thanmulti-line (higherenergy) events 27
3. Neutrino Oscillations: Track Selection zenith angle resolution: 0.8 degrees for multi-line events 3 degrees for single-line events Single-line Multi-line M.Spurio-MG13 @ Stokolm • Select pure sample of atmospheric neutrinos (<5% muon contamination) using a cut on the track fit quality • Blue: misreconstructedatmospheric muons • Green: atmospheric neutrinos • Red: neutrino withoscillations
3. Neutrino Oscillations: Result Systematics: (Absolute normalisation free) Absorption length: ±10% Detector efficiency: ±10% Spectral index of flux: ±0.03 OM angularacceptance 2008-2010 data (863 days): No oscillation: 2/NDF = 40/24 (2.1%) Best fit: 2/NDF = 17.1/21 Δm2 = 3.1 10-3 eV2 sin22 =1.00 5% error on slope vs ER/cosR ANTARES preliminary ANTARES preliminary 68%CL contours no osc ANTARES K2K Super-K MINOS M.Spurio-MG13 @ Stokolm best osc Assuming maximal mixing: Δm2=(3.1±0.9) 10-3 eV2 Accepted by PLB: arXiv:1206.0645
ANTARES infrastructure completed: Only operating deep sea neutrino telescope Largest neutrino telescope in the Northern hem. Operating smoothly, maintenance capability proven Good understanding of detector Important testbed for KM3NeT R&D and software Exciting and broad physics program …. Unexplored regions of sensitivity for gal. sources Steady/transient sources, monopoles, DM, oscillations … multi-messenger approach (optical, satellite, GW) Real-time readout and in-situ power capabilities a large program of multi-disciplinary activities: acoustics, biology, oceanography, seismology…… Major step towards the multi-kilometre cube deep-sea Neutrino telescope: KM3NeT Summary
Counting Rates (short timescale) 40K 2 min Continuous baseline: Radioactivity in the sea (40K) + bioluminescent bacteria Bursts: bioluminescence from Macroscopic organisms
AcousticPositioning Storey 1 Storey 8 Storey 14 Storey 20 Storey 25 Measure every 2 min: Distance line bases to 5 storeys/line and also storey headings and tilts Radial displacement Precision~ few cms
Absolute Pointing: Moon Shadow 884 days live time (2007-2010) M.Spurio-MG13 @ Stokolm 2.7 sigma significance Agrees with Monte Carlo expectations 34