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تسجيل مستخدم جديدPhoton yields from nitrogen gas and dry air excited by electrons
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In order to detect ultrahigh-energy cosmic rays (UHECR), atmospheric fluorescence light from the trajectory of the extensive air shower may be measured by mirror-photosensor systems. In this type of experiment the photon yield from electrons exciting air of various densities and temperatures is most fundamental information for estimating the primary energy of UHECR. An experiment has been undertaken using a Sr90 $beta$ source to study the pressure dependence of photon yields, and the life times of the excited states, for radiation in nitrogen and dry air. The photon yield between 300 nm and 406 nm in air excited by 0.85 MeV electrons is 3.73+-0.15 (+-14% systematic) photons per meter at 1000 hPa and 20 $^{circ}$C. The air density and temperature dependence is given for application to UHECR observations.
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The air fluorescence technique is used to detect ultra-high energy cosmic rays (UHECR), and to estimate their energy. Of fundamental importance is the photon yield due to excitation by electrons, in air of various densities and temperatures. After ou
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