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Atmospheric neutrino selection

Atmospheric neutrino selection. goal: improve efficiencies for both E -2 and atmospheric neutrinos strategy improved hitcleaning track resolution (paraboloid fit) zenith restricted fit Phit/Pnohit fit no neural networks (or similar). Efficiency of New Analysis.

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Atmospheric neutrino selection

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  1. Atmospheric neutrino selection • goal: improve efficiencies for both E-2 and atmospheric neutrinos • strategy • improved hitcleaning • track resolution (paraboloid fit) • zenith restricted fit • Phit/Pnohit fit • no neural networks (or similar) Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  2. Efficiency of New Analysis atmo. neutrinos 45 % E-2 neutrinos 40 % • efficiency > 60% above 120° relative to L2 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  3. Neutrino Candidates NatmoMC: ± 25% Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  4. Effective Area • zenith angle dependence new std. Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  5. Atmospheric Neutrinos • neutrino-effective area for energies above 50 GeV Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  6. Corrected Zenith Angle Spectrum • account for acceptance and oscillations SuperKamiokande: Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  7. systematic error Restrictions on Δm2? • neutrino flux relative to flux with Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  8. What do we expect from 6 years? • 10000 atmospheric neutrinos • study high energy • restrictions on alternative oscillation modells 90% with energies from 0.1 – 10 TeV Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  9. MedianRes, Zenith (hard cuts Qz> 110°) data 00-03 data 2000 data 2001 data 2002 data 2003 ... years behave differently number of dead OM‘s is important! Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  10. Lorentz invariance test Glashow - hep-ph/0407087 • neutrino species can have different maximal velocities v1, v2, v3 < c • velocity eigenstates rotated w.r.t. flavor eigenstates by v(and phase ) • define Ecritical = Ec=sqrt(m²c / 2v) E < Ec mass oscillation dominant Ec < E Lorentz violation dominant examine 2 extreme cases: case 1:velocity eigenstates = flavor eigenstates case 2:velocity eigenstates = mass eigenstates Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  11. AMANDA‘s range survival probability for a  for case 2 with Ec = 100 GeV Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  12. Case 1: Qv = 0 Ec = 1 GeV Ec = 10 GeV Ec = 100 GeV Ec = 1 TeV Ec = 10 TeV Ec = 100 TeV Ec = 1 PeV Ec = 10 PeV Ec = 100 PeV hardly accessible for AMANDA Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  13. Case 2: Qv = p/4 Ec = 1 GeV Ec = 10 GeV Ec = 100 GeV Ec = 100 TeV Ec = 1 TeV Ec = 10 TeV Ec = 1 PeV Ec = 10 PeV Ec = 100 PeV well accessible for AMANDA for Ec< 1TeV Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  14. Ec - cos(h) - plane exclusion regions case 2: (only 2002 data, preliminary) 90 % C.L. Ec ~ 102.5 = 316 GeV v/c ~ 1.2*10-26 log ( Ec / GeV ) 99 % C.L. Ec ~ 102.2 = 158 GeV v/c ~ 4.6*10-26 cos(h) Depends on assumed systematic errors (needs to be studied in detail) Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  15. Other studies There are many (exotic) models around that can be tested: Quantum decoherence  extra dimensions ... and lots of other ideas extensive ANTARES Monte Carlo study ... see Francis talk Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  16. Additional plots (not shown) Note: analysis 2000-2003 is very preliminary! Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  17. Standard Analysis • optimized for best sensitivity (E-2 – spectrum) • selected neutrinos 2002 • efficiencies Ndata = 470 NatmoMC= 402 ± 100 (for θ>90°) atmo. neutrinos 11 % E-2 neutrinos 28 % relative to L2 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  18. Efficiency of New Analysis atmo. neutrinos 45 % E-2 neutrinos 40 % • efficiency > 60% above 120° relative to L2 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  19. Ndata Ndata NatmoMC NatmoMC θ>90° 2021 1793 θ>90° 459 437 θ>110° 1194 1238 θ>110° 283 312 Neutrino Candidates Standard analysis New analysis NatmoMC: ± 25% Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  20. Effective Area • zenith angle dependence • energy dependence new std. new (for different spectra) new std. E-2 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  21. Atmospheric Neutrinos • neutrino-effective area • remaining background contribution to systematic error ~10% Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  22. Data 2000-2003 Level 5 data from Zeuthen 00-03 analysis Level 6a fits with T.Becka‘s hit cleaning pandel (seeded 32-Pandel) bayes (seeded 64-Bayes) PhPnh (seeded 10-PhPnh) ParabolaFit on PhPnh Softer cuts: Ldiff>25 spaceangle(JAMS,phpnh)<30 spaceangle(pandel,phpnh)<10 Smoothness > -0.4 MedianRes<5 „Soccer cut“ Hard cuts: Ldiff>30 spaceangle(JAMS,phpnh)<10 spaceangle(pandel,phpnh)<10 0.4 > Smoothness > -0.4 MedianRes<5 „Soccer cut“ Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  23. year 2000 2001 2002 2003 lifetime 197 193 204 213 events L6a 149,404 200,159 238,475 257,874 Qz>90°, flare<10, Irun 30,955 35,468 41,370 44,985 softer cuts Qz>90° 2309 2918 3195 3543 softer cuts Qz>110° 1075 1364 1574 1679 hard cuts Qz>90° 1075 1424 1690 1819 hard cuts Qz>110° 746 955 1138 1176 Data 2000-2003 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  24. GPS day vs. Zenith (no cuts) Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  25. Zenith vs. Cogz (no cuts) Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  26. Zenith vs. Cogz (hard cuts Qz> 90°) Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  27. MedianRes vs. Cogz (no cuts) Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  28. MedianRes vs. Cogz (hard cuts Qz> 90°) Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  29. spaceangle(JAMS,phpnh), spaceangle(pandel,phpnh),Ldiff, Smoothness -- (no cuts) data 00-03 data 2000 data 2001 data 2002 data 2003 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  30. spaceangle(JAMS,phpnh), spaceangle(pandel,phpnh),Ldiff, Smoothness -- (softer cuts Qz> 90°) data 00-03 data 2000 data 2001 data 2002 data 2003 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  31. spaceangle(JAMS,phpnh), spaceangle(pandel,phpnh),Ldiff, Smoothness -- (hard cuts Qz> 90°) data 00-03 data 2000 data 2001 data 2002 data 2003 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  32. spaceangle(JAMS,phpnh), spaceangle(pandel,phpnh),Ldiff, Smoothness -- (hard cuts Qz> 110°) data 00-03 data 2000 data 2001 data 2002 data 2003 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

  33. MedianRes, Zenith (hard cuts Qz> 90°) data 00-03 data 2000 data 2001 data 2002 data 2003 Jens Ahrens and Thomas Becka, Atmospheric Neutrinos, Berkeley, March 2005

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