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arXiv · 1408.5886

Experimental study of the microwave emission from electrons in air

E. Conti·G. Collazuol·G. Sartori
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Abstract

We searched for the emission of microwave radiation in the Ku band generated by a 95 keV electron beam in air. We unequivocally detected the radiation, and measured its yield and angular dependence. Both the emitted power and its angular pattern are well described by a model, where microwave photons are generated via bremsstrahlung in the free-electron atomic-nucleus collisions, during the slowdown of the electrons. As a consequence, the radiation is not isotropic but peaked in the forward direction. The emission yield scales proportionally with the number of electrons. This contrasts a previous claim that the yield scales with the number squared, due to coherence. With a Monte Carlo simulation we extrapolate our results to the Ultra High Energy Cosmic Ray energy range.

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E. Conti, G. Collazuol, G. Sartori. 2014-08-25. Experimental study of the microwave emission from electrons in air. https://doi.org/10.1103/physrevd.90.071102

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