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arXiv · 1401.4310

On the absolute value of the air-fluorescence yield

Abstract

The absolute value of the air-fluorescence yield is a key parameter for the energy reconstruction of extensive air showers registered by fluorescence telescopes. In previous publications, we reported a detailed Monte Carlo simulation of the air-fluorescence generation that allowed the theoretical evaluation of this parameter. This simulation has been upgraded in the present work. As a result, we determined an updated absolute value of the fluorescence yield of 7.9+-2.0 ph/MeV for the band at 337 nm in dry air at 800 hPa and 293 K, in agreement with experimental values. We have also performed a critical analysis of available absolute measurements of the fluorescence yield with the assistance of our simulation. Corrections have been applied to some measurements to account for a bias in the evaluation of the energy deposition. Possible effects of other experimental aspects have also been discussed. From this analysis, we determined an average fluorescence yield of 7.04+-0.24 ph/MeV at the above conditions.

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BibTeXRIS

J. Rosado, F. Blanco, F. Arqueros. 2014-01-17. On the absolute value of the air-fluorescence yield. https://doi.org/10.1016/j.astropartphys.2014.02.003

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