Complex Analysis of Askaryan Radiation: A Fully Analytic Treatment including the LPM effect and Cascade Form Factor

Jordan C. Hanson; Amy L. Connolly

doi:10.1016/j.astropartphys.2017.03.008

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arXiv · 1605.04975

Complex Analysis of Askaryan Radiation: A Fully Analytic Treatment including the LPM effect and Cascade Form Factor

Jordan C. Hanson·Amy L. Connolly

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Abstract

The Askaryan effect describes coherent electromagnetic radiation from high-energy cascades in dense media with a collective charge. We present an analytic model of Askaryan radiation that accounts simultaneously for the three- dimensional form factor of the cascade, and quantum mechanical cascade elongation via the Landau-Pomeranchuk- Migdal effect. These calculations, and the associated open-source code, allow the user to avoid computationally intensive Monte Carlo cascade simulations. Searches for cosmogenic neutrinos in Askaryan-based detectors benefit from computational speed, because scans of Askaryan parameter-space are required to match neutrino signals. The Askaryan field is derived from cascade equations verified with Geant4 simulations, and compared with prior numerical and semi-analytic calculations. Finally, instructive cases of the model are transformed from the Fourier domain to the time-domain. Next-generation in situ detectors like ARA and ARIANNA can use analytic time- domain signal models to search for correlations with event candidates.

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Jordan C. Hanson, Amy L. Connolly. 2017-04-26. Complex Analysis of Askaryan Radiation: A Fully Analytic Treatment including the LPM effect and Cascade Form Factor. https://doi.org/10.1016/j.astropartphys.2017.03.008

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