Speaker
Description
We present an updated cosmic-ray spectrum measured using the surface detector array of the Pierre Auger Observatory spaced at 433 m (SD-433). This denser array, compared to the two other arrays at Auger with 1500 m and 750 m spacing, lowers the threshold energy to 63 PeV. We measure the so-called second knee feature at (230 ± 50 stat ± 35 syst) PeV, where the spectral index increases from 3.00 ± 0.05 stat ± 0.10 syst to 3.32 ± 0.08 stat ± 0.10 syst. We discuss the systematic uncertainties of these spectral parameters. Additionally, we combine the spectra from the SD-433 and SD-750 arrays, encompassing the second knee and ankle features. Finally, we provide an overview of all spectra measured by the various detectors and techniques employed at the Pierre Auger Observatory.
