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On the measurement of the proton-air cross section using longitudinal shower profiles

Ralf Ulrich·Johannes Blümer·Ralph Engel·Fabian Schüssler·Michael Unger
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Abstract

In this paper, we will discuss the prospects of deducing the proton-air cross section from fluorescence telescope measurements of extensive air showers. As it is not possible to observe the point of first interaction $X_{\rm 1}$ directly, other observables closely linked to $X_{\rm 1}$ must be inferred from the longitudinal profiles. This introduces a dependence on the models used to describe the shower development. The most straightforward candidate for a good correlation to $X_{\rm 1}$ is the depth of shower maximum $X_{\rm max}$. We will discuss the sensitivity of an $X_{\rm max}$-based analysis on $σ_{\rm p-air}$ and quantify the systematic uncertainties arising from the model dependence, parameters of the reconstruction method itself and a possible non-proton contamination of the selected shower sample.

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Ralf Ulrich, Johannes Blümer, Ralph Engel, Fabian Schüssler, Michael Unger. 2006-12-08. On the measurement of the proton-air cross section using longitudinal shower profiles. https://doi.org/10.1016/j.nuclphysbps.2007.10.019

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