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RECENT RESULTS Andrea Silvestri University of California, Irvine

http://amanda.uci.edu. RECENT RESULTS Andrea Silvestri University of California, Irvine International School on Cosmic Ray Astrophysics 14 th Course: Neutrinos and Explosive Events in the Universe July 6, 2004 Erice-Sicily. THE AMANDA COLLABORATION ~ 150 members.

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RECENT RESULTS Andrea Silvestri University of California, Irvine

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  1. http://amanda.uci.edu RECENT RESULTS Andrea Silvestri University of California, Irvine International School on Cosmic Ray Astrophysics 14th Course: Neutrinos and Explosive Events in the Universe July 6, 2004 Erice-Sicily

  2. THE AMANDA COLLABORATION~ 150 members UNITED STATES: Bartol Research Institute, UC Berkeley, UC Irvine, Pennsylvania State UW Madison, UW River Falls, LBNL Berkeley EUROPE: VUB-IIHE Brussel, ULB-IIHE Bruxelles, Universite’ de Mons-Hainaut, Imperial College London DESY Zeuthen, Mainz Universitaet, Wuppertal Universitaet, Stockholm Universitet, Uppsala Universitet, Kalmar Universitet SOUTH AMERICA: Universidad Simon Bolivar Caracas ANTARCTICA: South Pole Station ISCRA 2004, JULY 6, 2004

  3. Airport MAPO AMANDA South Pole Dome ICECUBE Summer camp 1500 m Amundsen-Scott South Pole Station 2000 m ISCRA 2004, JULY 6, 2004

  4. THE AMANDA DETECTOR http://amanda.uci.edu AMANDA B-10 Inner core of AMANDA-II 10 STRINGS 302 OMs Data years: 1997-1999 OPTICALMODULE 8-inch Hamamatsu R591202 109 gain, 14 dynode stages PMT noise (300-1000)Hz AMANDA-II Present status of the detector 19 STRINGS 677 OMs Trigger rate ~ 80Hz Time resolution ~ 5ns AMANDA-II: astro-ph/0211269 ISCRA 2004, JULY 6, 2004

  5. PRINCIPLE OF NEUTRINO DETECTION O(10m) long electron tracks DOWN-GOING TeV-PeV electrons MUON FLUX FROM ISOTROPICns neEvent Cascade O(10cm) long electron tracks MeV positrons UP-GOING O(km) long muon tracks nm Event TeV Muons SN neEvent  12 m NO Event Reconstruction

  6. POLAR ICE = AMANDA MEDIUM SCATTERING ABSORPTION ICE BUBBLES DUST DUST labs ~ 110 m @ 400 nm lsca ~ 20 m @ 400 nm AVERAGE OPTICAL ICE PARAMETERS ISCRA 2004, JULY 6, 2004

  7. EXPECTED NEUTRINO (nm) FLUXES WB BOUND SCENARIOS CONSTRAINED BY: • Spectrum E-2 • Only CR above ankle • Bound on (nm + nm) intensities (CRandg) WB Bound assumptions: NEW AMANDA Bound BUT WB Bound may be exceeded if: • Sources are opaque • Topological Defects associated with small proton flux Phys. Rev. D64, 023002 (2001) n- FLUX CONSTRAINED BY CR OBSERVATION ISCRA 2004, JULY 6, 2004

  8. AMANDA SCIENCE COSMOLOGY – PARTICLE PHYSICS - ASTROPHYSICS Collaboration Analysis Policy: ‘blindness’ - cuts are optimized on fraction of data or on a time-scrambled data set (except for SN searches which are based on detector noise rate monitoring) ISCRA 2004, JULY 6, 2004

  9. DETECTOR CAPABILITIES & ENERGY RANGE MUONS: Angular resolution: 1.5o - 2.5o Energy resolution: 0.3-0.4 ( in log(DE/E)) Coverage: 2p CASCADES: Angular resolution: 30o - 40o Energy resolution: 0.1-0.2 ( in log(DE/E)) Coverage: 4p  effective area (schematic): -interaction in earth, detector response En 2 100 GeV 100 TeV 100 PeV AMANDA operates in different energy regimes: ISCRA 2004, JULY 6, 2004

  10. ATMOSPHERIC n & DIFFUSE FLUX LIMITS [nm] Neural Network energy reconstruction Regularized unfolding → energy spectrum AMANDA test beams: atmospheric n and m First spectrum > 1 TeV (up to 100TeV) Neutrino fluxes vs. Energy Neutrino Energy spectrum Volkova flux parameterizations 104 105 En (GeV) Last bin info to calculate the limit to Extraterrestrial E2 neutrino flux Previous analysis publication PRELIMINARY Phys. Rev. Lett. 90 251101 (2003) Includes 33% systematic uncertainty E2μ(E) < 2.58·10–7 GeV cm-2 s-1 sr-1 ISCRA 2004, JULY 6, 2004

  11. DIFFUSE FLUX SEARCH [CASCADES] 4π coverage for cascades • 2000 data sample (AMANDA-II) • 197 days livetime • 1.2·109 events @ trigger level • Simulated background • - atmospheric μ (920 d) • - atmospheric ν Event selection based on - topology - energy Model rejection factor optimized for E-2 signal After optimized cuts: Nobs = 1 event Natm μ = 0.90 Natm ν = 0.06 ± 25%norm +0.69 -0.43 +0.09 ­0.04 ISCRA 2004, JULY 6, 2004

  12. DIFFUSE FLUX LIMITS all [CASCADES] E2all  PRELIMINARY Sensitive to all three flavors Assuming E-2 signal spectrum E2all (E) < 8.6·10–7 GeV cm-2 s-1 sr-1 (flavor mixing e::=1:1:1) 50 TeV < Eν < 5 PeV Some AGN core production predictions excluded at 90% C.L. (see excluded predictions slide) ’00 paper submitted to Phys. Rev. D AMANDA-B10 publication Phys. Rev. D67, 012003 (2003) ISCRA 2004, JULY 6, 2004

  13. ULTRA HIGH ENERGY NEUTRINO Eν > 1016 eV Earth opaque → search in the upper hemisphere mostly close to horizon Bright events (high Nchannel) → low atm. μ background V-cross-section increases but → larger energy uncertainties Long μ tracks (>10 km) neutrino effective area vs. energy average all angles horizontal events PeV - EeV Low fraction of 1-p.e. hits Very effective for Bright events Train Neural Network with UHE-sensitive parameters to separate E-2 signal from atmospheric ν (CORSIKA) Simulated UHE event ISCRA 2004, JULY 6, 2004

  14. UHE NEUTRINO LIMITS all  PRELIMINARY 1997 data (AMANDA-B10)131 days livetime ν energy after cuts (from E-2) E2all  E2all  Amanda νμ ×3 E2all  Nobs = 5 events Nbgr = 4.6 ± 36% events Paper to be submitted assuming an E-2 flux (1 PeV < En < 3 EeV) : E2all (E) < 1.510-6 GeV cm-2 s-1 sr-1 (e::= 1:1:1) NO EXCESS OBSERVED AMANDA-II (2000): similar Aeff, gain in exposure time AMANDA-II (TWR 2003): expected further improvement using Waveforms ISCRA 2004, JULY 6, 2004

  15. DIFFUSE NEUTRINO FLUXES[nm] 5 & 6 Excluded predictions Model predictions and AMANDA (E-2) limits WB BOUND Volkova flux Parameterizations ISCRA 2004, JULY 6, 2004

  16. EXCLUDED PREDICTIONS Specific predicted model spectra excluded by AMANDA Stecker,Salamon (1996) prediction excluded by all these AMANDA analyses ISCRA 2004, JULY 6, 2004

  17. POINT SOURCE SEARCHES ν effective area vs. energy Atmospheric ν MC Optimize cuts in each declination band - assume E-2 signal spectrum - estimate BG from declination band Combined 2000+2001 analysis sensitivity vs. declination 2000+2001 better than single year by 1.6-1.8 2000 2001 2002 average flux upper limit [10-8cm-2s-1] Angular Resolution [median space angle] 1.5°(near vertical) - 2.7°(near horizontal) PRELIMINARY declination [°] 2000+2001 Phys. Rev. Lett. 92 071102 (2004) lim  1.3·10-8 cm-2s-1 declination averaged sensitivity(δ>0°) (integrated above 10 GeV, E-2 signal) : Now unblind & Add 2002 data → ISCRA 2004, JULY 6, 2004

  18. 3 YEAR AMANDA POINT SOURCE SEARCH Search for event excess in Northern sky: Search in 259 rectangular sky bins - bin size is zenith dependent 922 events [+ declination] All events = 1883 below horizon: mostly atmospheric ν PRELIMINARY (RA) 961 below the horizon above horizon: mostly fake events Livetime 2000: 197 days; 2001: 194 days; 2002: 213 days 2000+2001+2002:922 events No clustering observed → No evidence for point sources ISCRA 2004, JULY 6, 2004

  19. SOURCE SIGNIFICANCE SKY-PLOT MAP based on the 2000 + 2001+ 2002 DATA set Unbinned statistical analysis: use track resolution (pdf) for each event σ Combined sky-plot of Unscrambled events!! 922 events 922 EVENTS PRELIMINARY σ (RA) Scrambled events in Azimuth (RA) compatible NO EXCESSbeyond randomly expected Atmospheric Neutrinos! ISCRA 2004, JULY 6, 2004

  20. SEARCH FOR  CORRELATED WITH GRBs -1 hour +1 hour 10 min Blinded Window Background determined on-source/off-time Background determined on-source/off-time Time of GRB(Start of T90 ) Neutrinos produced in GRB environment: p +  ±m± + nme± + ne+ nm + nm Low background analysis due to space and time coincidence! • - GRB catalogs: BATSE, IPN3 & GUSBAD • - Analysis is blind: • finalized off-source (± 5 min) with MC simulated signal • BG stability required within ± 1 hour • PeV muon effective area (averaged over zenith angle)50,000 m2 ISCRA 2004, JULY 6, 2004

  21. GRB RESULTS Super-K (1454 BATSE Trig) A-II 2002 (44 BATSE trig) w/attenuation A-II 2002 (all bursts) A-II 2002 (weighted) BT = BATSE Triggered; BNT = BATSE Non-Triggered New = IPN log10(Φν/cm-2) For 312 bursts w/ Broken Power-Law Spectrum (Ebreak=100 TeV, Γ=300) 97-00 Flux Limit at Earth: PRELIMINARY E2Φν≤ 4x10-8 GeV cm-2 s-1 sr-1 log10(Eν/ eV) Green’s function Fluence Limit Paper to be submitted ISCRA 2004, JULY 6, 2004

  22. DARK MATTER SEARCH IN THE EARTH Sensitivity to muon flux from neutralino annihilations in the center of the Earth: Look for vertically upgoing tracks maximize sensitivity to WIMP signal Combine 3 years: 1997-99 Total livetime (80%): 422 days Muon flux limits PRELIMINARY New solar system WIMP diffusion estimates (Lundberg & Edsjö) Eμ > 1 GeV More realistic neutralino velocity distribution Disfavored by direct search (CDMS II) Lower μflux estimates Limit for “hardest” channel: Previous analysis publication No WIMP signal detected! Phys. Rev. D66, 032006 (2002) ISCRA 2004, JULY 6, 2004

  23. DARK MATTER SEARCH IN THE SUN AntaresandIceCubeare Just sensitivities and not limits Increased capture rate due to addition of spin-dependent processes Exclusion sensitivity from analyzing off-source bins 2001 data 0.39 years livetime PRELIMINARY Eμ > 1 GeV Best sensitivity (considering livetime) of existing indirect searches using muons from the Sun/Earth No WIMP signal detected! ISCRA 2004, JULY 6, 2004

  24. SUPERNOVA SEARCH (’97 + ’98) & ‘00 AMANDA-II AMANDA-B10 IceCube 30 kpc AMANDA-B10 with 302 OMs AMANDA-II with 677 OMs Selection of very stable OMs SN Signal proportional To number of OMs ! • B-10: 70% of Galaxy • A-II: 95% of Galaxy • IceCube: up to LMC CRUCIAL = LOW NOISE 215 Days live time; 90% = 9.8 kpc Simulation (IceCube) Count rates Joining SNEWS (SuperNova Early Warning System) [with Super-K, SNO, Kamland, LVD, Boone] • Recent online analysis software upgraded • Can detect 90% of SN within 9.4 kpc • less then 15 fakes/year 0 5 10 sec Analysis of 200x data in progress Upper Limits on SN Rate in the Galaxy 70% of Galaxy coverage sn < 4.3Event yr-1 Astropart.Phys. 16 (2002) 345 ISCRA 2004, JULY 6, 2004

  25. THE TWR SYSTEM Major Hardware Upgrade! Transient Waveform Recorder system installed between 2001/02 and 2003/04 campaigns • NEW TWR DAQ: • TWR= Transient Waveform Recorder • Last Season all channels instrumented!! • Data Volume: 15TB/Year • Trigger Rate ~ 150Hz (majority 18) • Negligible deadtime • Next Season: Software Trigger • DAQ dynamic range: • 150 Npe from primary pulse • 5000 Npe from afterpulse • Physics benefits: • Much larger dynamic range ~ x100 • Improved Energy reconstruction • Improved Angular resolution • Increased 1pe detection efficiency crucial for UHE/EHE physics ISCRA 2004, JULY 6, 2004

  26. HOW DO WE TREAT & PROCESS 15TB DATA? http://www.teragrid.org • What is SDCD? SAN DIEGO SUPERCOMPUTER CENTER • Research unit of the UC San Diego • Primarily funded by NSF • World’s largest computer! • World’s fastest computer! • 20 TeraFlops! • 1 PetaByte! • 40 Gigabits per second! • What is SRB? STORAGE RESOURCE BROKER • A network data storage system • SRB is virtually an unlimited storage system • Entire DATA set 2003: • AMANDA can use one of the most powerful computing resources on the planet • We sent over NETWORK 15TB data • Data can be store on hard-drive ‘forever’ • Data processing in a weekly time scale http://www.npaci.edu/DICE/SRB We can store our data: 15TB (2003) and 20TB (2004) for UNLIMITED SPACE & TIME!!! ISCRA 2004, JULY 6, 2004

  27. SUMMARY & OUTLOOK AMANDA hasn’t seen nsources yet, But “she” has produced a lot of Physics!! • Limits on diffuse neutrino fluxes (TeV-EeV) • Numerous results published on major scientific papers • For update: http://amanda.uci.edu • First results from AMANDA-II: • Three year Point source search (data set 00+01+02) • Improved Diffuse limits: cascades & unfolded spectra • Several predictions excluded • Combined analysis (2000-03) in progress • Papers on 1997-2000+ data in progress • Ice description mature • New TWR DAQ implemented → improved physics potential • SNDAQ upgrade → contribute to SNEWS ISCRA 2004, JULY 6, 2004

  28. BACKUP SLIDES ISCRA 2004, JULY 6, 2004

  29. SPASE/AMANDA: CR COMPOSITION SPASE-2 Iron Proton AMANDA (number of muons) log(E/PeV) SPASE-2 (number of electrons) AMANDA SPASE (scintillator array at 3000m) Shower core resolution: O(m) Shower direction resolution < 1.5o SPASE-2  electron AMANDA B10  muon Probes hadronic (m) and EM (e) energy in the primary shower  composition change around the knee Paper accepted by Astropart. Phys. Amanda-B10 / Spase-2 calibration: NIM A522 (2004) 347 ISCRA 2004, JULY 6, 2004

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