1 / 17

Search for EHE Neutrinos with IceCube Detector: Atmospheric Muon Flux and GZK Neutrino Surface Energy Study

Explore the IceCube detector's potential to detect EHE neutrinos by analyzing atmospheric muon flux uncertainty and GZK neutrino surface energy levels. The study includes data on muon bundles, energy loss processes, fluxes at different depths, waveform saturation effects, and empirical models. Comparison with CORSIKA proton and iron models is detailed, along with event selection criteria and sensitivity analysis for 2006 data. Discover the optimized cuts and background estimations to enhance EHE neutrino detection.

alta
Télécharger la présentation

Search for EHE Neutrinos with IceCube Detector: Atmospheric Muon Flux and GZK Neutrino Surface Energy Study

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Search for EHE neutrinoswith the IceCube detector Aya Ishihara for the IceCube collaboration Chiba University

  2. atmospheric muon flux above 106GeV is very uncertain EHE Neutrino Underground Surface n fluxes Target GZK neutrino Surface energy range 8 < Log(E/GeV) < 12 (energy at depth ~ 6-7< Log(E/GeV) < 10-11) atm m Fluxes at the IceCube depth main signal GZK neutrino induced leptons background Atmospheric muon Simple energy cut works! EGZK>>EAtm m S. Yoshida et. al. (2004) Phys. Rev. D 69 103004

  3. 9 EeV ? Energy ! mandttracks loose their energy by radiative processes 100 TeV pair-creation e+e- m p photo-nuclear e+e- m g bremsstrahlung

  4. The 9-stringreal sample2006Example Bright Events 20mV 0mV [ns] Digital optical module waveform (ATWD / FADC) NPE = integral of waveforms / single charge

  5. m t NPE and Energy Correlationwith 2006 IceCube configuration Visible Energy vs. NPE correlation up to log10 NPE ~ 4.5 the resolution is then diffused by waveform saturation effects log ( m Energy / GeV ) log ( t Energy / GeV )

  6. m Atmospheric Muon Bundles Model Number of muon in a shower above threshold Energy Ethres (Elbert parameterization) This relation between cosmic ray energies and the energy of the muon bundle fixes atmospheric muon bundle fluxes log Cosmic-Ray Energy Nagano, Watson: Reviews of Modern Physics Vol 72 No3 (689)

  7. Background simulation Partial experimental data atmospheric m simulation model 1 atmospheric m simulation model 2 log10NPE cos q 4 < log10NPE < 5

  8. Atmospheric fluxes at IceCube depth #2 #1 without GZK cutoff with GZK cutoff !! #1 #1

  9. Comparison with CORSIKA Atmospheric m empirical model Corskia Proton QGSJET01 Corsika Iron QGSJET01 log (m Bundle Energy at Depth [GeV]) log (Primary CR Energy [GeV]) proton and ion both underestimate the rate overestimate underestimate m bundle energy 10 PeV m bundle energy 1 PeV m bundle energy 100 TeV log (Primary CR Energy [GeV])

  10. Event Selection and Numbers number of events Atm. m GZK m GZK t

  11. Sensitivity for 2006 E2 fcut2 (106.5 < E < 109.5) ~ 10-6 [GeV cm-2 sr-1 sec-1] 90 % C.L. all n flavors added assuming 1:1:1 ratio

  12. Neutrino Effective Area average over full solid angle Cut level 2

  13. Summary • The IceCube 9 string array provided physics data sample in 2006 • MC shows 9 string IceCube is capable of EHE neutrino search but waveform saturation and its readout limits its capability • For BG estimation, Elbert formula, derived from experimental relation between EHE CR fluxes and surface mu bundle energy, used • Effective area, sensitivity of ~10-6 [GeV cm-2 sr-1 sec-1] for 2006 IceCube EHE region is obtained with optimized cuts with the assumption of zero background events from the empirical atmospheric m background model

  14. backup

  15. Comparison with CORSIKA Proton QGSJET01 Iron QGSJET01

  16. The 9-stringreal sample2006FADC Waveforms saturated

  17. NPE 20mV 0mV Integrating a waveform/single charge = NPE low gain EHE waveforms high gain 120mV 0mV + = 4.5V 0V 4.5V 0V

More Related