EAS data at the mountain level and a shape of the CR spectrum beyond the break

TL;DR

This paper investigates the limitations of current methods for deriving cosmic ray spectra from extensive air shower data, revealing a local maximum in the spectrum at high electron numbers and suggesting an additional component at energies above 10 PeV.

Contribution

It demonstrates the breakdown of traditional models for young EAS and identifies a local maximum in the EAS spectrum, indicating a possible new cosmic ray component at high energies.

Findings

EAS spectrum has a local maximum at N_e ~ 10^9.

Traditional models diverge for young EAS with N_e ≥ 10^7.

Evidence suggests an additional cosmic ray component above 10 PeV.

Abstract

In the most works which deal with EAS the CR energy spectrum is deduced by means of the model defined dependence $E_0=a\cdot{N_e}^{\alpha}$. An electron total number $N_e$ is evaluated by integration of the NKG-function f(r). This algorithm breaks down for young EAS with age parameter $s\sim0$. This work shows, that part of the young EAS becomes large in the range $N_e\geq10^7$, it cause to divergency of the $N_e$ integral for them and distorts the shape of EAS (CR) spectrum. A final analysis of the experimental data permits to conclude that EAS spectrum has local maximum at $N_e\sim10^9$, which results in a decrease of the EAS spectrum slope for $N_e\geq10^7$ (inverse break or "knee"). A local maximum can arise because of the additional CR component in the range $E_0\geq10$ PeV.