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Sky view of the Mediterranean sea telescopes

Sky view of the Mediterranean sea telescopes. FOV for up-going neutrinos. From Mediterranean 24h per day visibility up to declination d ~ -50°. >25%. >75%. C overage of most of the sky (87%) including the Galactic Centre. Galactic sources.

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Sky view of the Mediterranean sea telescopes

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  1. Sky view of the Mediterranean sea telescopes FOV for up-going neutrinos From Mediterranean 24h per day visibility up to declination d ~-50° >25% >75% • Coverage of most of the sky (87%) including the Galactic Centre R. Coniglione

  2. Galactic sources • SNR expected to be good candidates for high energy neutrinos (>1TeV) • The two best candidates with a high intensity and well measured gamma spectrum: SNR RXJ1713.7-3946 and Vela Jr (RXJ0852.0-4622) SNR RXJ1713.7-3946 Vela Jr (RXJ0852.0-4622) HESS Gamma spectrum HESS Gamma spectrum Source extension R=1° Measured up to 20 TeV Pure exponential a=-2.2 I (20TeV) = 1÷3 10-14 cm-2 s-1 TeV-1 Visibility 84% Source extension ~ R=0.5° Measured up to 100 TeV Cutoff in gamma energy I (20TeV) = 1.7 10-14 cm-2 s-1 TeV-1 Visibility 72% R. Coniglione

  3. Extension and energy cutoff dependence KM3NeT detector The source extension dependence homogeneous emission The energy cutoff dependence Discovery Sensitivity Discovery • Discovery flux increases of about a factor 2 for an extended source with R= 0.5° • Sensitivity (discovery) worsens by an order of magnitude when the cut-off energy decrease from 1PeV to 10TeV From KM3NeT Technical Design Report http://www.km3net.org/KM3NeT-TDR.pdf R. Coniglione

  4. 2pt autocorrelation analysis of the ANTARES data Sensitive to a large variety of source structures Relying on data only: systematic uncertainties different from MC based methods • Input: • Cumulative number of event pairs as function of their angular distance • Reference distribution from scrambled data sets

  5. 2pt autocorrelation analysis of the ANTARES data • Analysis: • Comparisonbetween data and reference distributions based on Li&Maformalism • Trial factor correction using pseudo experiments 2007-2008 data (selected for point source analysis) Maximum deviation of data from reference distribution 1.1s at DW<7° -> p-value =0.55 Any significant correlation found

  6. The bubbles The observation of high energy gamma from two well shaped giant Bubbles in the Milk Way is one of the recent most exciting discoveries • What mechanism can produce high energy gamma rays? • Are also high energy neutrinos produced? R. Coniglione

  7. The Fermi bubbles observation Fermi LAT observation Meng Su, Tracy R. Slatyer, Douglas P. Finkbeiner, Astrophys. J. 724 1044-1082, 2010 1 <Eg<5 GeV no spatial and intensity variation in the g spectrum Solid angle single bubble 0.34 sr 5 <Eg<50 GeV R. Coniglione

  8. g spectrum The g spectrum is flat in E-2 dN/dE and of high intensity (10-7÷ 10-6 GeV/cm2/s/sr) Mesured up to 100 GeV R. Coniglione

  9. A cartoon picture Bubbles observed also in X-ray and Microwaves In Meng Su et al. bubbles are explained as due to relativistic CR electrons that produce gamma through IC process R. Coniglione

  10. A new model: gammas from a “reservoir” of CR proton and heavy ions in the Galactic center From M. Crocker and F. Aharonian Phys. Rev. Lett. 106 (2011) 101102 “We show below that a cosmic ray population can explain these structures” ……… “…Finally, we predict that there should be a region of extended, TeV g radiation surrounding the Galactic nucleus on similar size scales to the GeV bubbles with an intensity up to E-2 Fg(TeV) ~10-9 TeV cm-2 s-1 sr-1which should make an interesting target for future g-ray studies. Likewise, the region is a promising source for future, Northern Hemiphere, km3-volume neutrino telescope: we estimate (assuming a g=2.0 proton spectrum cut-off 1 PeV)…. From simple calculations the expected neutrino flux is of the order of 10-7GeV cm-2 s-1 Is this flux visible with a high energy neutrino detector ? R. Coniglione

  11. KM3NeT detector lay-out Artist impression of KM3NeT • KM3NeT in numbers • (full detector) • ~300 DU • 20 storey/DU • 40m storey spacing • ~ 1 km DU height • ~ 180m DU distance • ~ 5 km3 volume The Storey Detection Units Primary Junction box Secondary Junction boxes Electro-optical cable The OM All the technical information in http://www.km3net.org/KM3NeT-TDR.pdf R. Coniglione

  12. The MC simulations Monte Carlo Simulations (same codes of ANTARES modified for a km3 detector) • Neutrino generation and interaction (CC & NC) + natm generation (Bartol flux) and interaction (CC & NC) (GENHEN) + matm (Mupage parameterization) • Light simulation (optical water properties) and hit generation (PMT simulation) (KM3 code) • K40 Background and electronics • Track reconstruction based on likelihood Discovery flux calculation • Minimization of Model Discovery Potential (MDP) optimizing on: L (related to the reconstruction quality), #hits (related to the muon energy), Rbin search cone R. Coniglione

  13. The neutrino generation Homogeneous generation in a circular region around fixed points (modified version of GENHEN code) Galactic coordinates Up going tracks Visibility North ~72% South ~ 83 % North d = -15° RA = 243° Radius =19° South d = -44° RA = 298° Radius =19° R. Coniglione

  14. Discovery flux Bubbles north + south KM3NeT detector of about 310 DU • ~months for the evidence (3s) • ~1 years to claim the discovery (5s) R. Coniglione

  15. Fermi bubbles in ANTARES Searches for neutrino from Fermi bubbles in ANTARES just started Reduced set of data used (about 1 month) (blind analysis) Comparison Data/Monte Carlo in progress (MUPAGE for atmospheric muon production, GENHEN for atmospheric neutrino and antineutrino production) Analysis similar to the diffuse flux analysis Background rejection: Atmospheric muons: cuts on the measured zenith angle, track reconstruction quality parameter and number of hits. Selection based on Monte Carlo. Atmospheric neutrinos: cuts on the R parameter related to the neutrino energy. Ri= number of hits on i-th PMT R = ΣRi / number of all PMTs contributing to the event Soft cuts applied up-going tracks L > -6 Nlines >1 Nhits >60 Angular error <1° Geometrical cuts • Data • MC natm • MC matm Preliminary

  16. Fermi bubbles in ANTARES Assuming a E-2 neutrino spectrum with intensity of 1 10-7 GeV cm-2 s-1 the expected observation time needed for the discovery (5s 50%) is of about 5 years PRELIMINARY RESULTS from MC

  17. Conclusions • Extended and very extended sources present in our galaxy -> appropriate analysis required • Fermi bubbles predictions very sensitive to the shape of the neutrino spectrum • Fermi bubbles ANTARES analysis on going • Good chance to see neutrinos from Fermi Bubbles R. Coniglione

  18. R. Coniglione

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