On the sensitivity of the spatial-angular distribution of the Cherenkov light in extensive air showers to the mass composition of primary cosmic rays with energies of $10^{15}$-$10^{16}$ eV

This paper analyses the possibility of separating distinct groups of nuclei of primary cosmic rays with energies of ${10}^{15}$-${10}^{16}$ eV from the data on the spatial-angular distribution of Cherenkov light in extensive air showers. The paper shows that using an array of a few (3–4) telescopes with a moderately sized angular cell ∼0.5° placed at a distance ∼100 m from one another, one can achieve almost complete separation of the showers initiated by these nuclei (the Bayesian classification error is a few percentage points for the case of separating primary protons and nitrogen nuclei). The authors propose new parameters of the angular Cherenkov image that can greatly enhance the separability of the shower classes as compared to the approach based on the traditional parameters.