Torino - 13/07/2010 LATEST RESULTS OF THE ANTARES HIGH ENERGY NEUTRINO TELESCOPE Tommaso Chiarusi INFN - Sezione Bologna on behalf of the ANTARES Collaboration
Physics with High Energy Cosmic νs SNR Binary systems neutrinos Microquasars Dark Matter? Exotics (magnetic monopoles, nuclearites) protons (50 Mpc) Galactic photons (10 Mpc) Extra Galactic AGN neutrons (unstables) GRB low energy particles
Neutrino Telescopes perform indirect measurements (Markov, 1960 ) PMTs lattice transparent media Cherenkov light charge current interaction ν μ N W μ X Upgoing μ incoming neutrino ν μ dense neutrino target track reconstruction from time and position of detected Cherenkov light assuming a θcherenkov = 43 in water
Sky coverage ANTARES > 75% 2 25% 75% < 25% TeV γ-sources galactic extragalactic IceCube 100% 0%
The ANTARES Collaboration ITEP, Moscow University of Moscow IFIC, Valencia UPV, Valencia, TUC, Barcelona NIKHEF, Amsterdam KVI Groningen NIOZ Texel CPPM, Marseille DSM/IRFU/CEA, Saclay APC Paris IPHC (IReS), Strasbourg Univ. de H.-A., Mulhouse Clermont-Ferrand IFREMER, Toulon/Brest C.O.M. Marseille LAM, Marseille University/INFN of Bari University/INFN of Bologna University/INFN of Catania University of Erlangen Reimes Sternwarte Bamberg. ISS, Bucarest GeoAzur Villefranche LNS Catania University/INFN of Pisa University/INFN of Rome University/INFN of Genova Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
The ANTARES Site Toulon La Seyne sur Mer Main cable (45km) Shore station
12 lines of 75 PMTs 25 storeys/line 3 PMTs/storey 885 active PMTs Instrumented volume 0.05 km 3 high PMT density so to have a good angular resolution and optimizing the effective area Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
Expected Performance (full detector) Neutrino effective area For E ν <10 PeV, A eff grows with energy due to the increase of σ ν and the muon range. For E ν >10 PeV the Earth becomes opaque to neutrinos. Angular resolution For E ν < 10 TeV, the angular resolution is dominated by the ν-μ angle. For E ν > 10 TeV, the resolution is limited by track reconstruction errors. N det =A eff Time Flux 8 A 0.3 deg angular resolution would imply a time precision better than 5 ns and OM position known to better than 2 m ANTARES actual time and spatial precisions: ~ 1.8 ns (= 1.3 ns TTS + 0.5 ns time calib.) on a 10 PMT and ~ 0.1 m for each OM!!
ANTARES deployment
Living under the sea: the uncorrelated single photon spurious signals Bursts in the rate from bioluminescence baseline ( 40 K + biolumin.) 40 K decays (constant) 40 khz/pmt(10, 0.5 p.e. thld) Bioluminescence (occasional) up to some MHz/PMT(10, 0.5 p.e. thld) + No beam crossing reference such as for experiments at Colliders + complex DAQ structures in extreme conditions (mandatory: minimal underwater maintaining) ALL DATA TO SHORE approach (up to 15 Gbps total)
Z(m) Acoustic Positioning Example for Sea current v= 25 cm/s r max = 22m Acoustic system 1 emitter (+ receiver) at each line socket 5 receivers along each line Compass and Accelerometer 1 Compass at each storey 1 Accelerometer at each storey mostly coherent movement of lines r(m) Measure every 2 min Acoustics: distance sockets - receivers Compass: Heading Accelerometer: tilt Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
Atmospheric muons and neutrinos p cosmic rays 5-line data (May-Dec 2007) + 9-12-line data (2008) µ νµ background 341 days detector live time 1062 neutrino candidates cosmic νµ νµ µ atmosphere Preliminary good agreement with Monte-Carlo expectation: upward-going: atmospheric neutrinos: 916 (30% syst. error) atmospheric muons: 40 (50% syst. Error) Zenith angle
Muon Depth Intensity Relation ANTARES data with 5 lines Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
Scrambled ANTARES Sky map of 1000 neutrinos Galactic coordinate System Earth coordinate System Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
Point source sensitivity Point source search with 5-lines data (2007) is close to be finalized. preliminary In the next weeks the ANTARES Collaboration will publish the relative upper limits Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
Dark matter searches 5-line data 2007 (68 days) 68 days detector live time Competitive with direct detection for SD cross section Flux Neutralino mass (GeV)
Diffuse Flux: energy estimator R = number of PMTs with prompt and late photons number of all PMTs contributing to the event muon cascade good slope for energy resolution
Diffuse Flux: unblindig the data events/bin 10 2 E test -7-2 = 10 GeV cm s -1 sr -1 Atms, no R cut Atms, R 1.31 Signal, no R cut Signal, R 1.31 1 νprompt (Bartol+RQPM) 10-1 90% 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 log 10 (E /GeV) R = number of PMTs with prompt and late photons number of all PMTs contributing to the event Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
Diffuse Flux: upper limit with 2007-2009 data preliminary MACRO: Astropart.Phys. 19:1-13,2003. BAIKAL, Astronomy Letters, 2009, Vol. 35, No. 10, pp. 651 662. AMANDA-II (807 d) Phys.Rev.D76:042008,2007 IceCube: Astrop. Phys. 20 (2004) 507 WB= Waxman & Bahcall, PRD59 (1999) MPR98, PRD 63 (2001) SDSS91: Phys. Rev. Lett. 66(91)2697 Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
Ongoing combined searches Receive GRB alerts from Satellites (Fermi, Swift...) search for coincident neutrinos within time window (~100 seconds) Send neutrino cluster alert for optical follow-up Trigger: multiple / HE single neutrino event; Reconstruction on-line (<10ms) Alert message to Tarot Telescope in La Silla (Chile) Tarot takes 6 images of 3 minutes immediately and after 1, 3, 9 and 27 days sending alerts to the ROTSE system (4 telescopes) since 3 months Correlation with AUGER source distribution investigate directional correlation of neutrinos and UHE particles Correlation with VIRGO-LIGO signals investigate correlation of neutrinos and gravitational waves Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
Conclsions ANTARES is continuously taking data has a broad physics program determined the most sensitive upper limit on diffuse flux complements the sky coverage of IceCube paves the way for KM3NeT Tommaso Chiarusi PCC 2010 - Torino 13/07/2010
THANK YOU! Essential Bibliography 1. T. Chiarusi and M. Spurio, 2010, High-Energy Astrophysics with Neutrino Telescope, European Physics Journal C 65, nn. 3-4, 649 2. J. A. Aguilar et al. Transmission of light in deep sea water at the site of the Antares neutrino telescope. Astropart. Phys. 23 (2005) 131-155. 3. P. Amram et al. Sedimentation and Fouling of Optical Surfaces at the ANTARES Site. Astropart Phys. 19 (2003) 253-267. 4. P. Amram et al. The ANTARES optical module. Nucl. Instr. Meth. A484 (2002) 369. 5. M. Ageron et al. Studies of a full scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements. Nucl. Instrum. Meth. A581 (2007) 695-708. 6. J. A. Aguilar, The Data Acquisition System of the ANTARES neutrino telescope, Nucl. Instrum. Meth. A 570 (2007) 107-116 7. A.Margiotta(ANTARESColl.), Systematic uncertainties in MonteCarlo simulations of the atmospheric muon flux in the 5-line ANTARES detector. Nucl. Instrum. Meth. A602 (2009) 76. arxiv:0809.0268 [astro-ph]. 8. G. Carminati, A. Margiotta, M. Spurio. MUons from Parametric formulas: A fast Generator of atmospheric μ-bundles for neutrino telescopes (MUPAGE). Nucl. Instr. Methods A602 (2009) 95 9. J.A. Aguilar et al, Zenith distribution and flux of atmospheric muons measured with the 5-line ANTARES detector, in press on Astropart. Physics (ASTROPARTPHYS-D-10-00029R2)
SPARE SLIDES
Observation of induced electromagnetic showers from muon tracks The light from EM shower is produced in one point on the muon path and it arrives delayed at PMT preliminary
ANGULAR RESOLUTION angular resolution = difference between reconstructed and MC generated angles vs. neutrino energy µ rec µ gener. dominated by kinema)cs ν µ rec ν gener. µ dominated by reconstruc)on angular resolu+on < 0.2 above 10 TeV limited tracking accuracy due to <me resolu<on: Light scaaering σ ~ 1.0 ns TTS in PMT σ ~ 1.3 ns <me calibra<on σ < 0.5 ns OM posi<on σ < 10 cm 25 ( σ < 0.5 ns)
THE ANTARES DETECTOR POSITIONING SYSTEM REAL TIME POSITIONING Acous<c posi<oning system + set of <ltmeters and compasses. Transceivers (RxTx) on the boaom of the lines, 4 autonomous transponders around the apparatus. 5 hydrophones (Rx) per line at specific heights. Tiltmeter and compass per storey, sound velocimeters (various depths). RECONSTRUCTION OF THE LINE SHAPE GLOBAL χ 2 FIT TO LINE SHAPE MODEL (BEHAVIOUR OF LINE: SEA CURRENT) Hydrophone posi)on rela)ve to line base loca)on (20 days) hydrophone Acoustic transceiver Acoustic transceiver Resolu)on be2er than 10 cm
TIME CALIBRATION Time difference between the LED OB and an OM 3 OMs σ = 0.4 ns 27 Op+cal LED beacon - Electronics + calibra)on σ ~ 0.5 ns - TTS in photomul)pliers σ ~ 1.3 ns - Light sca2ering + dispersion in sea water σ ~ 1.5 ns at 40 m Angular resolu+on 0.3 o (for E ν > 10 TeV ) Including the acous)c posi)on resolu)on and the ν- µ angle
ATTENUATION LENGTH MEASUREMENTS R min R max 28 The biggest challenge is to determine the separate contribu4on of absorp'on and sca*ering
IN SITU CALIBRATION WITH 40 K Integral under peak = rate of correlated coincidences γ Gaussian peak on coincidence plot Cherenkov γ e - (β decay) 40 K Peak offset 40 Ca 29 No dependence on bioluminescent ac<vity has been observed Cross check of <me calibra<on High precision (~5%) monitoring of OM efficiencies
Physics with High Energy Cosmic νs Understanding production mechanism ( cosmic accelerators ) of HE cosmic rays SNR Study very energetic objects: galactic: SN remnants, microquasars.. extragalactic: GRB, AGN, ; Search for Dark matter (wimps) Binary systems Exotic (magnetic monopoles, nuclearites) Microquasars Dark Matter? Exotics (magnetic monopoles, nuclearites) AGN GRB
Latest results of the ANTARES high-energy neutrino telescope The ANTARES high-energy neutrino telescope, fully functional since May 2008, is based on the detection of Cherenkov light produced in sea water by neutrinoinduced muons as well as electromagnetic or hadronic showers. It consists of a three-dimensional array of 885 photomultipliers distributed over 12 lines and installed at a depth of 2500 m in the Mediterranean Sea, 40 km off the French coast. The main goal of the experiment is the search for highenergy neutrinos from astrophysical sources such as AGNs, GRBs and SGRs or possibly from WIMP annihilation in the Sun or in the Galactic Halo. The telescope is sensitive to neutrinos with energy greater than few hundred GeV, with an effective area for upward muon detection which reaches 0.05 km2 at the highest energies. In this talk we review the current status of the detector; we give an overview on the atmospheric muon and neutrino analyses and present the first searches for point-like neutrino sources and diffuse flux of VHE neutrinos using data from Dec. 2007 to Dec. 2009. Abstract only for review this slide will be cut