The First LHAASO Catalog of Gamma-ray Sources below 25TeV

Abstract

We report the first catalog of TeV gamma-ray sources realized with the most sensitive wide field-of-view TeV telescope ever built. Since March 2021, it continuously surveys the northern sky with field of view ∼ 2 sr and >90% duty cycle. Using 508 days data collected by full array of LHAASO-WCDA, 69 sources were detected significantly, including 5 extra-galactic sources. 19 of these sources have no known TeV counterpart within 0.5 degree. In this paper, detailed analysis will be presented including background estimation, searching strategy and summary of the catalog.