The Cosmic Ray Spectrum of Light Component above 10TeV Measured by LHAASO Experiment
2019 July 22
One of main scientific goal of Large High Altitude Air Shower Observatory (LHAASO) is to measure individual cosmic ray spectra from 30 TeV to several EeV. The absolute energy scale obtained from the moon shadow measured by WCDA will be transferred to WFCTA at around 10 TeV. So it is important to measure the energy spectra of pure proton and proton&helium from 10 TeV to 100 TeV. The first and the second SiPM based Cherenkov telescopes of LHAASO have successfully put into operation in January and May 2019, respectively. The first water Cherenkov pool (150 m×150 m) of LHAASO (WCDA-1) also began operation in February. The combined detection of showers with WCDA-1 and Cherenkov telescopes enables LHAASO to improve the resolution of reconstructed energy, shower direction, shower core location and composition identification. The energy threshold of WFCTA is well below 10 TeV. The preliminary analysis results of the data are presented in the paper with comparison with the corresponding simulation of the air showers their detection by the telescopes.