Experimental study of the microwave emission from electrons in air

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.

arXiv comment5 pages, 4 figures. Accepted for publication in Phys.Rev.D

References in corpus (12)

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• Detection and imaging of atmospheric radio flashes from cosmic ray air showers
• New air fluorescence detectors employed in the Telescope Array experiment
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• Search for microwave emission from ultrahigh energy cosmic rays
• Simulations and theory of radio emission from cosmic ray air showers
• The MIDAS telescope for microwave detection of ultra-high energy cosmic rays
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Cited by in corpus (8)

• Radio detection of cosmic ray air showers in the digital era
• First Experimental Characterization of Microwave Emission from Cosmic Ray Air Showers
• Radiowave Detection of Ultra-High Energy Neutrinos and Cosmic Rays
• An Estimate of the Spectral Intensity Expected from the Molecular Bremsstrahlung Radiation in Extensive Air Showers
• Molecular Bremsstrahlung Radiation at GHz Frequencies in Air
• On the coherent emission of radio frequency radiation from high energy particle showers
• The AMY (Air Microwave Yield) experiment to measure the GHz emission from air shower plasma
• Considerations on the radio emission from extended air showers