1 / 32

Olaf Scholten KVI, Groningen

Ultra-High Energy Cosmic ray and Neutrino Physics using the Moon. Olaf Scholten KVI, Groningen. Large Area ??. Area = 2 10 7 km 2. Use the Moon!!. Principle of the measurement. Cosmic ray. Detection: Westerbork antennas. 10 7 km 2. 100MHz Radio waves. Detection off the Moon.

cliftonj
Télécharger la présentation

Olaf Scholten KVI, Groningen

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. Ultra-High Energy Cosmic ray and Neutrino Physics using the Moon Olaf Scholten KVI, Groningen ARENA 2008

  2. Large Area ?? Area = 2 107 km2 Use the Moon!! ARENA 2008

  3. Principle of the measurement Cosmic ray Detection: Westerbork antennas 107 km2 100MHz Radio waves ARENA 2008

  4. Detection off the Moon Goldstone Lunar UHE Neutrino Search (GLUE) P. Gorham et al., PRL 93, 041101 (2004) First experiment: 12 hrs using single Parkes 64m dish in Australia: T. Hankins et al., MNRAS 283, 1027 (1996) Two antennas at JPL’s Goldstone, Calif. Tracking Station @ 2.2 GHz, 123 hours ARENA 2008

  5. ~2 m Cosmic ray ~10 cm shower Wave front Askaryan effect: Coherent Cherenkov emission • Leading cloud of electrons, v  c Typical size of order 10cm Coherent Čerenkov for ν 2-5 GHz cos θc =1/n , θc=56o for ∞ shower length • Length of shower, L  few m Important for angular spreading ARENA 2008

  6. Angular spread Z0~Δc~λ/L=1/Lν D. Saltzberg et al PRL 86 (2001) 2802 Askaryan effect: confirmation in sand Experiment at SLAC with beams of photons And 1010 e-/bunch: effective shower energies 0.06-1.10 1019 eV 1 Jy = 10-26 W/m2/Hz ARENA 2008

  7. Based on physics principles Old parametrization Spreading around Cherenkov-cone n=1.8 GHz Sine profile L=1.7 m , E=1020 O.S. etal., Astropart.Phys. 2006 ARENA 2008

  8. Reflection Spreading is diminishing internal reflection 3 GHz 100 MHz ARENA 2008

  9. Cosmic rays, Position on Moon Calculations for Ecr=4 1021 eV 100 MHz 3 GHz Partial Detection probability With decreasing ν : - increasing area - increasing probability ∫over surface Moon D ν-3 Normalized distance from center ARENA 2008

  10. Detection Limits, Cosmic rays Minimum Flux for detecting 1 count/100h Detection threshold = 500Jy Decreasing ν: • Increasing threshold like ν-1 • Increase sensitivity like ν-3 ARENA 2008

  11. NuMoon Experiment @ WSRT Use Westerbork radio observatory • Advantages: • 117-175 MHz band • 25 m diameter dishes • 5 degree field of view • 12-14 coincident receivers • 500 hour observation time • 40 M samples/sec (PuMa2) • Polarization information ARENA 2008

  12. NuMoon Experiment @ WSRT Use Westerbork radio observatory 4 frequencies ARENA 2008

  13. Processing Pipeline • 18 TB raw data per 6 hr slot • Excision of narrow-band interference • De-Dispersion of ionosphere with GPS TEC values • Indentification of peaks in time spectrum • Data reduction 100:1 to 180 GB ARENA 2008

  14. + dedispersion ARENA 2008 Trigger: 4σ pulse in all four frequency bands

  15. ARENA 2008

  16. Trigger Power Spectrum Effect successive steps in analysis Gaussian noise ARENA 2008

  17. Prelimenary Results Analysis of 10 h 40 min data Additional observation time: 7 June +10h ARENA 2008

  18. NuMoon Experiment @ LOFAR • Total collecting area 0.5 km2 • Cover whole moon, • Sensitivity 25 times better than WSRT. • Bands: • 30-80 MHz (600 Jy) • 115-240 MHz (20 Jy) ARENA 2008

  19. Neutrinos WSRT, 100 hours 0 counts LOFAR, 30 days ~60 counts Theoretical predictions: Waxman-Bahcall limit GZK induced flux Phys.Rev.D64(04)93010 ARENA 2008

  20. Future: SKA,LORD 1 year observation, LFB: 100-300 MHz MFB: 300-500 MHz From: O.S., SKA Design Study report ARENA 2008

  21. SKA-Hadrons ARENA 2008

  22. z=5 z=20 z=50 Resonant neutrino absorption 30 day Neutrinos are absorbed on relic neutrino background by forming Z-boson A. Ringwald, L. Schrempp, JCAP 0610 (2006) 012 Measured pulse-height spectrum can distinguish sources at various distances OS& A. van Vliet,JCAP06(2008)015 ARENA 2008

  23. Conclusions NuMoon @ WSRT Future: NuMoon @ LOFAR NuMoon @ SKA Competitive Sensitivity for cosmic rays and neutrinos NuMoon NuMoon collaboration: O.S., Stijn Buitink, Heino Falcke, Ben Stappers, Kalpana Singh, Richard Strom ARENA 2008

  24. LORD efficiency for neutrinos ARENA 2008

  25. The observed Universe ARENA 2008

  26. Some distance scales • Nearest star, Proxima Centauri – 4 LY • Diameter of our galaxy – 100,000 LY • Distance to nearest galaxy – the Sagittarius dwarf galaxy, which • is being “eaten” by the Milky Way – 80,000 LY • Size of our “Local Group” – a collection of at least 30 galaxies, • including Andromeda – 3 Million LY • Size of our “Local Supercluster” which contains our Local Group, • the Virgo Cluster, and others – 100 Million LY • 1pc = 3.26 LY ARENA 2008

  27. Case: Shower @ 2.50 with surface Calculations for Ecr=4 1021 eV Influence of frequency Simulations for Moon Minimal signal = 3000Jy 0.1 GHz 85% of area 2.2 GHz 0.8% of area ARENA 2008 Intensity v.s. cos θ, φ

  28. Shock wave acceleration Colliding galaxies “Fermi shock acceleration” proton passes several times through shock front due to magnetic field. Spectrum  E -2 Active galactic nucleus Need large scale magnetic fields ARENA 2008

  29. Short-range particle astronomy • Larmor radius for a charged particle (charge Z) and energy E (1020 eV) in a magnetic field with strength B(nG): ρ(Mpc)=108·(E/1020eV)·(1/BnG)·(1/Z). • Galaxy about 1000 nG; proton escapes; iron wanders around From: M. Teshima 2006 ARENA 2008

  30. ARENA 2008

  31. Greisen – Zatsepin - K’uzmin (GZK) Transport Energetic protons loose energy through Interactions with the cosmic microwave background ARENA 2008

  32. Possible Sources within 1.5 MpcLocal Group ARENA 2008

More Related