Antares collaboration & location

1. ANTARES neutrino telescope status and indirect searches of Dark MatterGuillaume LambardCentre de Physique des Particules de MarseilleFrance

2. Antares collaboration & location

3. 12 lines (900 PMTs) 5 sectors/line 5 storeys/sector 3 PMTs/storey storey ~2500 m ~350 m instrumented 14.5 m ~40 km EOC Site/ Seyne-sur-Mer ~100 m Junction box ~70m EMC The Detector SCM P ~ 250 bars

4. A detection storey

5. Antares detection principle WATER Čerenkov cone Detector 42° FLOOR µ track Time local coincidences between OMs and Storeys -> Time hits distributions Vs Detection locations Charged current interaction µ ROCK

6. Observable sky by Antares at the latitude of ~43° ANTARES galactic coordinates skymap of visibility Galactic center position 90° -180° 180° -90°

7. Antares.com : Breaking news March 2006 : First line connected September 2006 : Line 2 January 2007 : Lines 3-5 December 2007 : 10 Lines on the site ~May 2008 : Whole detector

8. Physical expected performances E <~10TeV : kinematic E >~10TeV : the detector • Angular resolution < 0.3° (E>~TeV) limited by: • TTS in photomultipliers : σ~ 1.4 ns • Time Calibration : σ ~ 0.6 ns • Line positioning : σ < 10cm (σ < 0.5 ns) • Scattering and chromatic dispersion : σ < 1.0 ns

9. Physical expected performances For 12 lines Earth opacity for E > 100 TeV Increase with energy

10. Reconstruction results Case of ten lines reconstruction for a down-going event: m • Θ= 124.0° • Track projection in phase space (z,t)

11. Reconstruction results Case of ten lines reconstruction for an up-going event: m • q= 51.9°

12. Reconstruction results Hits distribution over zenith and azimuth angles Discrepancies MC/data Work on the OMs acceptance in progress… Azimuth angle  detector topology effect on the hits distribution At 12 Lines, the detector will be symmetric and this effect should disappeared in part

13. Reconstruction results All events Reconstruted up-going events Reconstructed Quality factor : Quality cut dertermined after Monte-carlo studies to discritimate the real up-going events with the down-going and misreconstructed events

14. Dark Matter search perspectives in the Sun ANTARES WIMP  Accretion into the sun Self-annihilation Sun Eν MWIMPs

15. Dark Matter search perspectives in the Sun Dark Matter indirect detection side – independent-model: • WIMPs traking down into heavy bodies by elastic scaterring and gravitational accretion • Self-annihilations into primary and secondary neutrinos • Interaction neutrinos/matter into the source-body • Neutrinos oscillations from the source to the Earth • Neutrinos/Earth medium charged current interactions -> muons • Effective Area, neutrinos flux and source visibility -> number of events

16. Annihilation rate and channels WIMPs lose energy through an elastic scaterring off nucleons into the Sun medium Equilibrium for Capture rate = annihilation rate  α (1000 GeV / mB(1))-6 *tanh2(mB(1)-13/4) Considered channels : • Primary neutrinos cc→nn, dN/dE = (1/Mc)², UED model • Secondary neutrinos (Bertone, Servant, Sigl) from • cc→ qq → p+/- → nm → enenmnm, • heavy quarks decay (before Hadronization) : b, c, t • t leptons and doublet of higgs dd* • And WW, ZZ for neutralinos(MSSM, mSugra, etc...) • Muon flux: (GeV-1.m-2.an-1) Oscillation over 3 flavorsne/nμ/ntfrom the Sun to the Earth

17. UED model UED model(Universal Extra-Dimensions): Every fields of the Standard Model propagate into the extra-dimensions (conventional space-time + 1 space dimension with a compactification scale to R constraints by the accelerator experiments) • Conservation of the Kaluza-Klein parity in effective 4-dim theory • KK lightest state → Dark Matter candidate LKPs (Lightest KK Particles), non-baryonic and neutral particles corresponds to the first KK-resonance level of the hypercharge boson B (1)where (Servant-Tait) : • self-annihilation channels : B(1) B(1)ff, hh, , p, e+, e- ,

18. Expected muons from DM self-annihilation Sun visibility for Antares in zenith angle Anticipated atmospheric bkg neutrinos per sec. Upward going part 400GeV<MLKP<1TeV Relic density r0 = 0.3 GeV/cm3 vLKP~220 km.s-1 sSD~10-6pb Compared to the atmospheric background ~5 evts for 3° in cone aperture around the Sun Expected muons events from the B(1) self-annihilations

19. Sensitivity of Antares to neutrinos from the Sun In the mSugra assumptions (at 12 lines) PRELIMINARY Lower limit from the « soft channel » (cc->bb) Upper limit from the « hard channel »(cc->WW) Updates for 5 & 10 lines configuration in progress…

20. Dark Matter annihilations in mini-spikes • Detection of neutrinos from Dark Matter annihilations into the mini-spikes around Intermediate Mass Black Holes (IMBHs) • Mini-spikes -> bright sources of neutrinos • Mini-spikes from the reaction of DM mini-halos to the formation of IMBHs • IMBHs model study MIMBHs~ 105 M๏ • Better sentivity and high energy resolution of ACTs(HESS, INTEGRAL, CANGAROO,…) can be used to discriminate mini-spikes from the ordinary Astrophysical sources. But the full surveys favored the sea neutrino telescopes(Antares & IceCube). • The location of Antares and an effective area of 1km2 appears to be the best for the detection-> Good perpectives for KM3-net

21. Mini-spikes ramdom distribution in the milky way ANTARES galactic coordinates skymap of visibility Galactic center position Equatorial coordinates skymap of IMBHs in one random realization (red diamonds) and 200 realizations (blue diamonds) with a great concentration around the Galactic Center (yellow circle)

22. Prospects from mini-spikes assumptions Prospects for detecting Dark Matter with neutrino telescopes in Intermediate Mass Black Holes scenarios – G. Bertone arXiv:astro-ph/0603148v2

23. Conclusions & perspectives PRELIMINARY Galactic coordinates skymap of 116 up-going events • Through a precise time calibration and acoustic positioning of the lines, we are able to extract : • a full sky map and potentials spikes positions into the neutrinos distribution with an integrated data taking time > 300 days (5 & 10 lines configurations take into account) • put limits over the LSP, LKP, etc… Dark Matter candidates masses by Sun, GC correlations the events direction through blind and unblind strategies (interesting for signals at low statistics) • Good perpectives from the IMBHs models and growths of mini-spikes around. But, difficulty to discriminate the neutrinos flux from Dark Matter self-annihilations to the classic Astrophysical events. Needed a crosscheck with the GRs data.

24. BACK UP

25. Expected neutrino flux from the Sun • Neutralino LSP in mSugra theory • mSugra parameter space through: m0,m1/2,A0,tan(b),sign(m) Expected neutrinos flux from the source Expected neutrinos events All models studied 0,094 < Ωh² < 0,129 (WMAP 3yr constraint) Ω h² < 0,094 All models studied 0,094 < Ωh² < 0,129 (WMAP 3yr constraint) Better signal

26. Backup:In situ calibration quality Coincidences rates through the 40K decay (40K 40Ca + e- + e): Coincidences between adjacent optical modules Čerenkov photons produced by relativistic electrons 40K  40Ca + e-  2γ Adjacent floor coincidences : Integral under the peak ~ muon flux Shape is sensitive to angular acceptance of optical modules andangular distribution of muon flux

27. Backup:LED Beacons Illuminations Examples and view of in situ calibration by the LED beacon system in the sea. The mean of these distributions centered around ~0 check the good quality of the time calibration before the deployment. Events t ( ns) Events t ( ns)

28. Backup : Background noise expected… Muons distribution over zenith angle

29. Backup : Trigger • Before to really reconstruct a muon track, there are five data processing levels from the data taking to the discovering of potential events: • Level 0 (L0) : All hits • Level 1 (L1) : local trigger search • local coinciding hits in a time gate (~20 ns) on 2 PMTs of the same floor • and/or all hits with charge > threshold param. (~2.5 p.e.) • Level 2 (L2) : global trigger search • Space-time relation between signals due to unscattered light from the same muon trajectory or bright point • assuming: high relativitic muons, slowest possible speed c/n (n~1.35). For two hits, causality implies: Δt : time between hits Δx : diff. Between PMTs positions

30. Backup : Trigger • Level 2 (L2) : • if the number of correlated hits > “minClusterSize” parameter(~4)  Cluster • For example for a 3D Trigger: • Minimum number of hits in the cluster = 5 • Minimum number of floors in the cluster = 5 • Minimum charge of the largest hits in the cluster = 0.3 p.e. • etc… • Level 3 (L3) : merging of overlapping events • each event contains a snapshot of all hits in a time window around the cluster • tmaxCausal ~ 2.2 μs • All hits within causality condition added • Level 4 (L4) : event building • All raw hits collected in a snapshot and combined into “PhysicsEvent” with data of clusters

31. Backup : Trigger • After, all processing levels used into different forms of triggers which look for: • 1D : time correlated hits in a given direction (L0 data in input) • 3D : time correlated hits from any directions (L1 data in input) • MX : similar to 1D + one local coincidence (1 L1) to speed up the processing of L0 data • And the number of L0 or L1 levels for each trigger can vary… • At the end, the muon track reconstruction strategy can apply to the selected hits…

32. Backup : Reconstrustion Strategy • Step 1 : Linear prefit by χ²-minimization over local coincidences and integrated charge of hits • step 2 : M-estimator minimization • Ai = charge, ri = time residual, fang = angular factor, K=0.05 (MC simulation) • step 3 : Likelihood-maximization A likelihood cut is preformed to discriminate the « real » up-going events compare to the down-going muon misreconstructed.

33. Backup : Neutrinos Effective Area

34. Backup : Neutrinos cross sections σcc, from CTEQ coll. Parton Distribution Functions

35. Backup : Reconstruction results Last case with five Lines:

36. Backup : Reconstruction results run 25685, frame 81559 3D reco. (A. Heijboer)

37. Backup : Energy reconstruction Factor 2 or 3 at low energy (<O(TeV))

38. Backup : Sun Case • Systematical analysis of data through an angular cut (dominated by the angular resolution at low energy) and an common ON/OFF area method. The up-going neutrinos events extracting into a 2° cone around the Sun position • Likelihood cut • Sun position computation into the topocentric(zenith and azimuth angle) and geocentric(declination, right ascention) frames, and eventually the apparent diameter to improve the cone aperture-> Common SLALIB library through an Antares ROOT Kit analysis dedicated

39. Backup : Sun Case Apparent diameter ~0.53°-> angular resolution still dominates Possibility to evaluate an expected background spectrum in zenith angle from the atmospheric neutrinos interactions