1 / 23

Surface Wave Propagation Preliminary work developing a method for surface wave detection

Surface Wave Propagation Preliminary work developing a method for surface wave detection. Amy Zheng. Ultrahigh Energy Neutrino Detection. UHE neutrinos will emit coherent radio frequency radiation that create the Askaryan effect [1].

parker
Download Presentation

Surface Wave Propagation Preliminary work developing a method for surface wave detection

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. Surface Wave Propagation Preliminary work developing a method for surface wave detection Amy Zheng

  2. Ultrahigh Energy Neutrino Detection • UHE neutrinos will emit coherent radio frequency radiation that create the Askaryan effect[1] • Signal strength is reduced due to ice’s absorption of bulk waves[2]

  3. Surface Waves as a Detection Tool • In tandem with existing experiments ARA[4], ARIANNA[5], and ANITA[6] ARIANNA ANITA ARA

  4. Surface Waves as a Detection Tool • Radiation from Askaryan cascade trapped in dielectric-dielectric layer between ice and air[3]

  5. Why Use Surface Waves? • ~800 times more efficient than bulk waves[7] • Amplitudes fall at the rate • Attenuation length times > bulk waves • Claimed by ARIANNA[6] • If detection is viable, expanding existing experiments would be far less expensive • No drilling

  6. Experimental Signatures • JPR claims • Signal strength for surface propagation > bulk propagation

  7. Procedure • 1 sending + 2 receiving antennas • Oscilloscope displayed waveshape • Physically moved antennas and recorded phase distance • n calculated from λ • Not pure far-field

  8. Example Antenna Placements • “Air” • “Surface” • “In”

  9. Translating to refractive index Definition of Refractive Index

  10. Refractive Index from Relative Phase Measurements

  11. Sand 1000MHz Sand Bulk n=1.73

  12. Sand Bulk n=1.73

  13. Salt Bulk n=2.4

  14. Salt Bulk n=2.4

  15. Amplitude as a Function of Distance

  16. Half orientation • Contains constructive and destructive interference • Other antenna positions show higher attenuation

  17. Air

  18. In

  19. Surface

  20. Measurement Complications • Imprecise measurements due to hand & eye observation • Sand tended to collect in the connectors • Angular error from planar disparity • Background EM noise & reflections often interfered

  21. Future Steps • Experiment using ice as a medium • Increase antenna size (requires larger volume) • Amplify signal for far field measurements • Perform experiments in the Hutchinson salt mine (Dec. 2012) • Verify • Coax Zenneck waves

  22. Acknowledgments • Dr. Besson • Marie Piasecki • Jordan Hanson • Andrew Johnannsen

  23. References [1]G.A. Askaryan, Sov. Phys. JETP 14, 441 (1961) [2]Physics of Ice Core Records: 185-212 (2005) [3]J.P. Ralston, Phys. Rev. D 71, 011503 (2005) [4]For information on ARA, see http://ara.physics.wisc.edu/ [5]For information on ARIANNA, see http://arianna.ps.uci.edu/ [6]For information on ANITA, see http://www.phys.hawaii.edu/anita/. [7]Jordan Hanson, “Developing the Next Generation of UHE Neutrino Detectors in Antarctica” I. H. Malitson. Interspecimen Comparison of the Refractive Index of Fused Silica, J. Opt. Soc. Am. 55, 1205-1208 (1965) doi:10.1364/JOSA.55.001205 Colloquium Notes from John P. Ralston

More Related