1 / 27

ANTARES: Towards Acoustic Detection of Highest Energy Neutrinos

ANTARES: Towards Acoustic Detection of Highest Energy Neutrinos. Kay Graf for the ANTARES Collaboration Erlangen Centre for Astroparticle Physics VLV n T 09, Athens, Oct. 13 th – 15 th 2009. Outline. Motivation The AMADEUS System Positioning Source Reconstruction. Motivation.

drea
Download Presentation

ANTARES: Towards Acoustic Detection of Highest Energy Neutrinos

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. ANTARES: Towards Acoustic Detection of Highest Energy Neutrinos Kay Graf for the ANTARES Collaboration Erlangen Centre for Astroparticle Physics VLVnT 09, Athens, Oct. 13th – 15th 2009

  2. Outline • Motivation • The AMADEUS System • Positioning • Source Reconstruction Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  3. Motivation Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  4. Ultra-high Energy Neutrino Astrophysics at energies above 1014-15eV: • universe becomes opaque to photons at Mpc range • CR protons, nuclei are galactic up to ~1018eV, suffer GZK cut-off above that • neutrinos unabsorbed at all energies → sources exist to at least 3x1020eV • UHE neutrinos are the only viable messenger beyond the local universe n viable throughout these regions P. Gorham Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  5. Highest Energy Neutrinos water/ice Cherenkov telescopes complementary techniques 10-4 • astrophysics: origin of UHECR GZK neutrinos • cosmology: top-down scenarios topological defects • particle physics: neutrino cross section TD 10-6 Flux × E2 [eV m-2 s-1 sr-1] 10-8 10-10 14 16 18 20 22 24 log10(E[eV]) T. Karg, arXiv:astro-ph/0608312 • for GZK n: >100km2 ∙ 2p ∙ year detector needed Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  6. neutrino (U)HE  Detection Methods • balloon • satellite • telescope  cascade m sonic wave  cascade opticalCherenkov radio Cherenkov  PMT array antenna array hydrophone array Optical Cherenkov water, ice latt < 100m Radio Cherenkov ice, salt, rock latt ~ 1km (ice) Acoustic Detection water, ice, salt latt > 1km (water) + hybrid detectors Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  7. Acoustic Signal Properties shower maximum Ecasc= 1 EeV @ 1km peak pressure (mPa/EeV) distance along shower axis (m) log10 (radial distance (m)) log10 (radial distance (m)) Acorne Coll. astro-ph/0704.1025 T. Karg, astro-ph/0608312v1 bipolar signal (~10kHz) with disk-like geometry Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  8. Simulations of an Acoustic Detector 200 acoustic antennas/km3 • strong dependence: Veff(Pthres) • Pthres mainly given by ambient noise • a threshold of 5mPa seems reachable in the deep-sea Pthres T. Karg, arXiv:astro-ph/0608312 Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  9. The AMADEUS System Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  10. The AMADEUS Project Feasibility Study • detector environment (hybrid) • detector calibration functionality • sensor design and positioning • background studies • signal processing techniques integration of acoustic setup into the ANTARES neutrino telescope Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  11. F ANTARESsite The ANTARES Neutrino Telescope • optical Cherenkov Telescope • 875 PMT • at 2500m water depth • Vinst~ 200 x 200 x 400 m3 Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  12. The AMADEUS System • taking data since 5-Dec-2007 • completely installed since 30-May-2008 • acoustics on L12: data from 6-Sep to 24-Dec 2008 “pingers“ (acoustic RxTx) on each anchor Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  13. AMADEUS Facts • characteristics • 36 sensors at 6 storeys (1 – 350m distance, 34 active) • 16bit @ 250kSps sampling • ~ -125dB re 1V/mPa sensitivity • ~85-90% uptime • data acquisition • all data to shore • raw: 20 MByte/s (1.5 TByte/d) • filtered: 0.3 MByte/s (4 GByte/d), up to now: 4 TByte • excellent stability of all DAQ parts Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  14. noise and transient additional tails ~60dB S/N (SINAD), no significant crosstalk Data Samples: Amplitude Histograms noise at different sensors • gaussian profile • linear correlation between sensors (factor ~ 99%) Samples (per ADC count) Samples (per ADC count) Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  15. Positioning Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  16. Positioning: Method for Reconstruction use emissions from the ANTARES acoustic positioning system (not directly connected with AMADEUS) • → positioning of individual sensors: • use absolute time from > 3 pingers:| rreception – remission | = cs¢(treception – temission – toffset) • treception by threshold crossing of signal envelope • temission from positioning system • → position/orientation by fitting storey geometry Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  17. Positioning: Example • 5 days of data • completely independent derivation of heading Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  18. Acoustic Modules (AMs)‏ Piezo sensors + preamplifiers design allows for integration of acoustic sensors into pressure housing of photo sensors  no need for additional mechanical structures Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  19. Pinger Signals for Reconstruction of Hydrophones and AMs AMs Hydros signal quality of AMs slightly degraded w.r.t. hydrophones(coupling, ringing of sphere, ...) Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  20. Positioning with AMs 4 5 1 0 2 3 • calculate difference of individually reconstructed sensor position • some issues/systematics need to be investigated Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  21. Heading on AM Storey Sensors 0 and 2 • systematic effects due to orientation of sensors w.r.t. pingers need to be investigated • for two sensors with distance at 250mm (in a sphere) better than 10° resolution reachable Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  22. Positioning Option for KM3NeT • AMADEUS-like acoustic sensors have the potential to combine: • positioning • investigation of acoustic neutrino detection techniques • marine science • Acoustic Modules (AMs) allow for an integration of acoustic sensors into Opto-Acoustical Modules (OAMs). • First Measurements in the Lab: • no significant degradation of performance of acoustic sensors by ANTARES HV base • noise expected mainly from DC-DC converter Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  23. Source Reconstruction Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  24. Source Direction Reconstruction: A Dolphin most probable source direction 1 0 -1 90 0 -90 • beam forming or time difference algorithms used • uncertainty <1° (mainly due to binning in the algorithm) Intensity (au)  (°) Amplitude (au) -180 0 180 0 0.5 1 f (°) time (ms) Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  25. Angular Distribution of Marine Sound Sources • direction reconstruction for one storey • all types of transient signals included • origin points horizontal to north • one month of data Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  26. Tracking of a Source • reconstruction with one storey • all triggered events within 500s displayed Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

  27. Summary • at UHE neutrinos are the only viable messenger beyond the local universe • need a >100km2 ∙ 2p ∙ year detector • acoustic detection promising candidate • complementary to optical and radio techniques (hybrid detection) • AMADEUS in ANTARES: feasibility study for a future acoustic detector • dedicated array in a detector environment – hybrid detection possible • successfully operated since 12/2007 • return of experience for future arrays (opto-acoustical?) Funded by: Kay Graf (ECAP) – VLVnT 09, Athens – October 2009

More Related