دانلود رایگان مقاله تفسیر اندازه گیری از تعداد میون در آزمایش ایرشاور گسترده

ABSTRACT

In this paper we analyze the energy evolution of the muon content of air showers between 1018.4 and 1019.6 eV to be able to determine the most likely mass composition scenario from future number of muons measurements. The energy and primary mass evolution of the number of muons is studied based on the Heitler–Matthews model and Monte Carlo simulation of the air shower. A simple model to describe the evolution of the first and second moments of number of muons distributions is proposed and validated. An analysis approach based on the comparison between this model’s predictions and data to discriminate among a set of composition scenarios is presented and tested with simulations. It is shown that the composition scenarios can be potentially discriminated under the conditions imposed by the method. The discrimination power of the proposed analysis is stable under systematic changes of the absolute number of muons from model predictions and on the scale of the reconstructed energy.

6. Conclusion

In this paper, we have analyzed the muon content of air showers, proposed a parametrization of the first two moments of the number of muons with energy and primary particle mass and showed how the measured mean and σ of log10Nμ can be used to discriminate between composition scenarios. We proposed a model to describe log10 Nmeas μ  and σ[log10 Nmeas μ ] as a function of energy and primary particle mass (A). This model was conceived to keep the most relevant hadronic interaction uncertainties concentrated in only two parameters (a and b). We have validated the model with Monte Carlo simulation of the air shower and its capability to describe the log10 Nmeas μ moments was proven. Six composition scenarios were considered. The particle flux predicted by these scenarios was transformed into the corresponding log10 Nmeas μ  and σ[log10 Nmeas μ ] evolution with energy. The log10 Nmeas μ  and σ[log10 Nmeas μ ] evolution with energy was fitted using the proposed parametrization. A comparison of the log10 Nmeas μ  and σ[log10 Nmeas μ ] model using a simple χ2 test allows the discrimination between the scenarios. The discrimination is effective even considering the systematic uncertainties on the Nμ prediction and on energy scale uncertainty