Speaker
Description
The main goal of AugerPrime is to extend the Pierre Auger Observatory’s sensitivity to cosmic ray composition into the flux suppression region of ultra-high energy cosmic rays (UHECRs) above 10$^{19}\,$eV. This involves enhancing the measurement capabilities of existing surface detectors to better distinguish between the muonic and electromagnetic components of air showers. Accurate methods to extract this information are crucial. To validate and refine these methods, the Underground Muon Detector (UMD) offers a direct measurement of the muon component for a sample of showers observed by the upgraded surface-detector array. In this work, we use Extensive Air Shower simulations over the 750$\,$m array of AugerPrime to estimate surface muon density and its correlation with muonic signals detected by $\text{Water}~\text{-}~\text{Cherenkov}$ Detectors (WCDs). We examined the relationship between signals from UMD simulations and Monte Carlo-generated densities at the WCDs from CORSIKA showers, parameterizing it based on the primary particle's energy, zenith angle, and distance from the shower axis. The resulting surface muon density estimation is highly accurate, with a bias closely centered around zero and a resolution of approximately 25$\%$ at energies around 10$^{17.8}\,$eV at 450$\,$m from the shower core, improving further at higher energies and closer to the shower axis. Additionally, a positive linear correlation between the estimated surface muon density and the simulated muonic signal in the WCDs was identified. This study aims to enhance future estimations of surface muon density from UMD data and support the development of methods to estimate the muonic signal using AugerPrime surface detectors.
