The Large High Altitude Air Shower Observatory (LHAASO) is built at an altitude of 4410 meters in Daocheng, Sichuan Province, China. As one of its major components, the Water Cherenkov Detector Array (WCDA) will focus on surveying the Northern sky for gamma-ray sources in a wide energy range. Because most of the triggered events are induced from hadronic cosmic-rays, suppressing a large number of background events is very important for LHAASO-WCDA. I'll introduce the delicate separation methods we used in data analysis and the preliminary Crab energy spectrum results we got for now.

Xiaojie Wang received her doctorate from the High Energy Physics Institute and mainly works on the data analysis aspect for the LHAASO-WCDA experiment.