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Parameterisation of lateral density and arrival time distributions of Cherenkov photons in EASs as functions of independent shower parameters for different primaries

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 نشر من قبل Umananda Dev Goswami
 تاريخ النشر 2018
  مجال البحث فيزياء
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The simulation of Cherenkov photons lateral density and arrival time distributions in Extensive Air Showers (EASs) was performed with the CORSIKA code in the energy range: 100 GeV to 100 TeV. On the basis of this simulation we obtained a set of approximating functions for the primary $gamma$-ray photons, protons and iron nuclei incident at zenith angles from 0$^circ$ to 40$^circ$ over different altitudes of observation. Such a parameterisation is important for the primary particle identification, for the reconstruction of the shower observables and hence for a more efficient disentanglement of the $gamma$-ray showers from the hadronic showers. From our parameterisation analysis, we have found that even though the geometry of the lateral density ($rho_{ch}$) and the arrival time ($t_{ch}$) distributions is different for different primaries at a particular energy ($E$), at a particular incident angle ($theta$) and at a particular altitude of observation ($H$) up to a given distance from the showe core ($R$), the distributions follow the same mathematical functions $rho(E,R,theta,H) = a E^{b}exp[-{c R + (theta /d)^{2}-f H}]$ and $t(E,R,theta,H) = l E^{-m}exp(n/R^{p})({theta}^q+s)(u {H}^2+v)$ respectively but with different values of function parameters.

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