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

Ultrahigh Energy Neutrino Detection Particles with velocity > will emit radiation due to the Askaryan effect [1] Detection is difficult due to internally reflected waves dying off quickly [2]

Surface Waves as an Detection Tool Radiation from Askaryan cascade is trapped in Air- dielectric layer between ice and firn [2] In tandem with existing experiments RICE [3] and ANITA [4]

Why Use Surface Waves? Surface waves travel between two mediums [5] ▫Amplitudes fall at the rate ▫Attenuation length times > bulk waves ~800 times more efficient than bulk waves If detection is viable, expanding existing experiments would be far less expensive Surface waves may carry information about neutrinos and their interactions with ice better than the current method

Procedure 1 sending + 2 receiving antennas displayed waveshape Physically moved antennas to determine wavelength and thus index of refraction

Example Antenna Placements “Surface” “In” “Air”

Translating to refractive index (1) (2) Definition of Refractive Index Sellmeier Equation

Refractive Index of Air Calculated (2) 1000MHz & 1500MHz n= [6] Single or Half λ λ (cm)

Refractive Index of Water (rms) Calculated (2) n~1.3333[7] Single or Half λ λ (cm)

Refractive Index of NaCl (rms) Single or Half λ λ (cm) Calculated (2) n~1.544[8]

Refractive Index of Granulated Fused Silica (sand) Calculated (2)1000MHz n= [9] Calculated (2) 1500MHz n= Single or Half λ λ (cm)

Refractive Index of Granulated Fused Silica (sand) Calculated (2) 1000MHz n= [9] Calculated (2) 1500MHz n= Multiple λ λ (cm)

Measurement Complications Mechanical water waves appeared to alter EM waveform Imprecise measurements due to hand & eye observation Sand and water tend to collect in the connectors Angular error from planar disparity Waveforms disappeared & reappeared on and off Waveforms constantly shift amplitude Background EM noise & reflections often interfered

Future Steps Experiment using ice as a medium Change antenna size; more precision Change experimental scale

References [1] G.A. Askaryan, Sov. Phys. JETP 14, 441 (1961) [2]J.P. Ralston, Phys. Rev. D 71, (2005) [3] RICE Collaboration, I. Kravchenko et al., Astropart. Phys. 19, 15 (2003); S. Razzaque, Sseunarine, D.Z. Besson, D.W. McKay, J.P. Ralston, and D. Seckel, Phys. Rev. D 65, (2002); Phys. Rev. D 69, (2004). [4] For information on ANITA, see [5] J. P. Ralston “An Experiment to Detect Surface Waves on Polar Ice” (2005) [6] Philip E. Ciddor. Refractive index of air: new equations for the visible and near infrared, Appl. Optics 35, (1996) doi: /AO [7]P. Schiebener, J. Straub, J.M.H. Levelt Sengers and J.S. Gallagher, J. Phys. Chem. Ref. Data 19, 677, (1990) [8] Faughn, Jerry S., Raymond A. Serway. College Physics, 6th Edition. Toronto: Brooks/Cole, 2003: 692. [9] I. H. Malitson. Interspecimen Comparison of the Refractive Index of Fused Silica, J. Opt. Soc. Am. 55, (1965) doi: /JOSA [misc] Colloquium Notes from John P. Ralston Refractive index calculations for relative reference only: ▫n found for granulated fused silica was found using Sellmeier constants for solid fused silica; granulation affects density. ▫Calculated n for water is for λ of nm ▫Calculated n for NaCl is for λ of 589 nm

Acknowledgements Dave Besson Marie Piasecki Carolyn Bandle