The Large High-Altitude Air Shower Observatory (LHAASO) officially published its first catalog of gamma-ray sources in the Astrophysical Journal Supplement Series on Feb. 27. The first LHAASO catalog contains 90 very-high-energy (VHE) gamma-ray sources, 32 of which are new VHE sources, significantly increasing the number of gamma-ray sources in the VHE band. It also contains 43 ultra-high-energy (UHE) gamma-ray sources, increasing the number of known UHE gamma-ray sources by three factors. UHE gamma-ray sources have become the best candidates for revealing the origin of cosmic rays. It is also revealed that pulsar wind nebulae are highly efficient UHE emitters in the Milky Way. Since the arXiv preprint version was released, more than 66 citations on inspire have accumulated. This work was carried out by the LHAASO Collaboration, with all four corresponding authors coming from the Institute of High Energy Physics of the Chinese Academy of Sciences, Dr. XI shaoqiang, Dr. HU shicong, Prof. CHEN songzhan and Prof. ZHA min.

LHAASO is a complex array and one of China’s major national scientific and technological facilities. It aims to conduct cosmic ray and gamma-ray observation and research. Based on its wide field of view, high duty cycle, and very high sensitivity, LHAASO can monitor 1/7 of the entire sky at any given time and scan 2/3 of the entire sky every single day. LHAASO’s Water Cherenkov Detector Array (WCDA) and Kilometer Square Array (KM2A) have been established as the most sensitive VHE/UHE gamma-ray full-sky survey instruments in the world, respectively.

As data accumulate, the sensitivity of the instruments will further improve and more VHE/UHE gamma-ray radiation sources will be identified soon.

Fig. 1: Significance maps from the LHAASO first catalog.

Paper link：https://iopscience.iop.org/article/10.3847/1538-4365/acfd29