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Particle Physics with ANTARES

Particle Physics with ANTARES. Pheno10 Madison-WI, 11-5-2010. Juan de Dios Zornoza (IFIC, CSIC - U. de Valencia). Neutrino Astronomy. Photons and protons are the “ traditional ” probes to study the Universe Neutrino telescopes are a complementary tool : Advantages :

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Particle Physics with ANTARES

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  1. Particle Physics with ANTARES Pheno10 Madison-WI, 11-5-2010 Juan de Dios Zornoza(IFIC, CSIC - U. de Valencia)

  2. Neutrino Astronomy • Photons and protons are the “traditional” probestostudytheUniverse • Neutrino telescopes are a complementarytool: • Advantages: • They are not absorbed bymatterorradiation (contrarytophotons and protons) • They are notdeflectedbymagneticfields (contrarytoprotons) • They are stable (contrarytoneutrons) • Disadvantages:hugedetectors are needed (miillions of tons) to observe them  n  p

  3. ANTARES • The ANTARES detector is located in the Mediterrean Sea (42º50’N, 6º10’E) at 2500 m deep, close to Tolon (France). • The Galactic Centre is observable by ANTARES Visibility GC Shore station in the M. Pacha Institute

  4. ANTARES detector • 12 lines (~900 PMTs) • 25 storeys / line • 3 PMTs / storey Buoy Horizontal layout Storey 14.5 m 350 m Detector completed in May 2008 Junction box 100 m Electro-optical cable ~60-75 m Readout cables

  5. Installation

  6. Connection Victor (remotely operated) Nautile (manned)

  7. Pictures from the seabed Detector layout

  8. Example of neutrino detected Example of a neutrino-candidatedetectedbyseverallines (up-goingevent) Hit height time Signal in each of the 12 lines of the detector

  9. Skymap for 2007-2008 data • 2007+2008 data (blinded): more than 1000 neutrino candidates

  10. IndirectSearch of DarkMatter

  11. Dark matter in the Sun  • WIMPs would scatter elastically in the Sun or Earth and become gravitationally trapped. • They would annihilate producing standard model particles. • Among the annihilation products, only neutrinos can reach us. ann: annihilation rate per unit of volume ann: neutralino-neutralino cross-section v: relative speed of the annihilating particles : neutralino mass density m: neutralino mass

  12. DM: analysismethod Cone size is optimized before unblinding to minimize average upper limit (sensitivity) using Feldmand-Cousin. Фν90%(mχ,α), ‘hard’ annihilation: • Optimum cone size depends on the assumed mass for neutralino: Mx=100 GeV  ~8 deg Mx=1000 GeV  ~5 deg mχ = 100 GeV mχ = 1000 GeV “hard” annihilation : χχ -> W+W- “soft” annihilation : χχ -> bb

  13. Limitswith 5-line period • mSUGRA parameter space not reached yet but… • only 68 active days included in this analysis and • only ~half of the detector

  14. SensitivitytomSUGRAmodels Focus point models Based on 3 years of full ANTARES data taking using standard reconstruction Background calculated fromatmospheric neutrinos + muonsinside 3° cone around the Sun’s position Inputs: -mSUGRA from DARKSUSY+ISASUGRA -Top quark mass: 172.5 GeV -Local halo density: 0.3 GeV/cm3

  15. Comparisonwithotherexperiments Comparison to Spin-independentdirect detection experiments Comparison to Spin-dependentdirect detection experiments 15

  16. Neutrino oscillations

  17. Strategy for neutrino oscillations • No differential distributions used (fragile)‏ • No energy measurements • Simple event counting • Use double ratios (most systematic effects cancel)‏ (see Kamiokande early 90's)‏ Two channels used: 3D (Multi-line sample)‏ 1D (Single line)‏ R1 = N(oscillation)1D/N(no-osc)1D R3 = N(oscillation)3D/N(no-osc)3D

  18. Elevation and energydistributions • Single line events less energetic • More affected by oscillations • Energy threshold at about 15 GeV = 75m = 6 floors • Single line events more vertical, larger L • More affected by neutrino oscillations

  19. E/L • Angular and energy effects enhance when considering E/L (equivalent to E/sin) • Single string events more affected by oscillation

  20. R1 and R3 behaviour No oscillations Full oscillations No structure visible when moving from no to full oscillations 3D Distinct maxima washed out by large width of distributions 1D Old analysis One order of magnitude shift for transition between 1D and 3D SK And then the idea is to compare N1D/N3D from data with the prediction from MC assuming oscillations or not-oscillations  preliminary estimate shows that we could reject the no-oscillations scenario with 3 sigmas

  21. Magneticmonopoles

  22. Fast magnetic monopoles Direct emission above Cherenkov threshold bM.M. > 0.72 Very large number of emitted light compared to a muon with the same velocity (~8500 times more). • Selection of only upgoing reconstructed events (qzen < 90°). • Remove most of misreconstructed events with the track fit quality factor tc². • Selection applied on the number of storeys (NHit) used in the track fit.

  23. Slow magnetic monopoles Indirect Cherenkov emission from d-rays for bM.M. > 0.51 d-rays provide detectable photons emitted within a large spread angle distribution. Modification of the reconstruction algorithm to implement a fit on the velocity. (L > 0 for M.M. & L~ 0 for n,m) Evtsreconstructedwith a velocity of ~ 0.55. m (1 year) M.M. with bsim~0.55 (arbitrarily normalised) n (1 year) Number of events

  24. Sensitivity to magnetic monopoles Expected sensitivities for one year of data taking of the 12-line detector. Preliminary Fast monopoles: Analysis based discriminant variables is competitive with present limits for high b. Analysis mostly finished, being refereed internally Slow monopoles: Analysis based on variable bis also sensitive for high b Improvements in the velocity fit and in the selection criteria are ongoing.

  25. Nuclearites

  26. Nuclearites • Massive lumps of strange quark matter originating in energetic astrophysical sources • Slow moving particles, with β~10-3 • Elastic collisions with the atoms of the media • Signal: black body radiation emitted at visible wavelengths by the thermal shock wave • A nuclearitewould cross the full Antaresdetector in about 1ms • Current triggers select only snapshots from simulated nuclearite events, for Mnucl≥1015GeV • A dedicated slow particle trigger will enable us to identify and reconstruct such exotic particles

  27. Nuclearites Data in a snapshot satisfies the trigger condition (for 12 lines: a linear combination of L0 hits & L1 hits ), thus: • Record all raw data for about 20 ms (as for GRBs, but much shorter) • Issue a warning to the group, that will download the data and analyze the event off-line. From Dec. 2008 data analysis, we expect ~5 triggers per day, ~1 GB/month (based on the size of GRB files)

  28. Conclusions • ANTARES was completed in May 2008 and is smoothly taking data • The mail goal is neutrino astronomy, but particle physics are also in the agenda • Dark matter signal in neutrino telescopes would be very clean. Best prospects in “focus point” • Other topics (oscillations, magnetic monopoles, nuclearites) are also under the scope. • New ideas are welcome!

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